IGCSE/O-Level
Computer Science
0478/2210
Past Pape rs /Ma rk Sche mes 2009- 2014
For more notes and papers
Iteach.pk
M.Mushtaq
LGS,GSIS,Appl es
T el : 0 3 2 1 5 2 7 5 2 8 1
Syllabus content at a glance
3.
1
Syllabus content at a glance
All candidates study the following topics.
Sections
Topics
Section 1
Theory of Computer Science
1.1 Data representation
1.1.1 Binary systems
1.1.2 Hexadecimal
1.1.3 Data storage
1.2 Communication and Internet technologies
1.2.1 Serial and parallel data transmission
1.2.2 Security aspects
1.2.3 Internet principles of operation
1.3 Hardware and software
1.3.1 Logic gates
1.3.2 Computer architecture and the fetchexecute cycle
1.3.3 Input devices
1.3.4 Output devices
1.3.5 Memory, storage devices and media
1.3.6 Operating systems
1.3.7 High- and low-level languages and their
translators
1.4 Security
1.5 Ethics
Section 2
Practical Problem-solving and
Programming
2.1 Algorithm design and problem-solving
2.1.1 Problem-solving and design
2.1.2 Pseudocode
2.2 Programming
2.2.1 Programming concepts
2.2.2 Data structures; arrays
2.3 Databases
6
M.Mushtaq
Cambridge O Level Computer Science 2210. Syllabus
for examination in 2015.
03215275281
Assessment at a glance
2
4.
Assessment at a glance
For Cambridge O Level Computer Science, candidates take two components: Paper 1 and Paper 2.
Components
Weighting
Paper 1: Theory
1 hour 45 minutes
60%
This written paper contains short-answer and structured questions. There is no
choice of questions.
No calculators are permitted in this paper.
75 marks
Externally assessed.
Paper 2: Problem-solving and Programming
1 hour 45 minutes
40%
This written paper contains short-answer and structured questions. There is no
choice of questions. 20 of the marks for this paper are from questions set on the
pre-release material.1
No calculators are permitted in this paper.
50 marks
Externally assessed.
Availability
This syllabus is examined in the June and November examination series.
This syllabus is available to private candidates.
Detailed timetables are available from www.cie.org.uk/examsofficers
Centres in the UK that receive government funding are advised to consult the Cambridge website
www.cie.org.uk for the latest information before beginning to teach this syllabus.
Combining this with other syllabuses
Candidates can combine this syllabus in an examination series with any other Cambridge syllabus, except:
•
syllabuses with the same title at the same level
•
0478 Cambridge IGCSE Computer Science
Please note that Cambridge O Level, Cambridge IGCSE and Cambridge International Level 1/Level 2
Certificate syllabuses are at the same level.
1
The pre-release material will be made available to Centres six months before the examination. It will also
be reproduced in the question paper. Candidates are not permitted to bring any prepared material into
the examination.
M.Mushtaq
Cambridge O Level
Computer Science 2210. Syllabus for03215275281
examination in 2015.
7
3
6.
Syllabus content
Syllabus content
Section 1 Theory of Computer Science
1.1
Data representation
Candidates should be able to:
1.1.1 Binary systems
•
recognise the use of binary numbers in computer systems
•
convert denary numbers into binary and binary numbers into denary
•
show understanding of the concept of a byte and how the byte is used to measure memory size
•
use binary in computer registers for a given application (such as in robotics, digital instruments
and counting systems)
1.1.2 Hexadecimal
•
represent integers as hexadecimal numbers
•
show understanding of the reasons for choosing hexadecimal to represent numbers
•
convert positive hexadecimal integers to and from denary
•
convert positive hexadecimal integers to and from binary
•
represent numbers stored in registers and main memory as hexadecimal
•
identify current uses of hexadecimal numbers in computing, such as defining colours in Hypertext
Markup Language (HTML), Media Access Control (MAC) addresses, assembly languages and
machine code, debugging
1.1.3 Data storage
•
show understanding that sound (music), pictures, video, text and numbers are stored in different
formats
•
identify and describe methods of error detection and correction, such as parity checks, check
digits, checksums and Automatic Repeat reQuests (ARQ)
•
show understanding of the concept of Musical Instrument Digital Interface (MIDI) files, jpeg files,
MP3 and MP4 files
•
show understanding of the principles of data compression (lossless and lossy compression
algorithms) applied to music/video, photos and text files
M.Mushtaq
Cambridge O Level
Computer Science 2210. Syllabus for03215275281
examination in 2015.
9
Syllabus content
1.2
4
Communication and Internet technologies
Candidates should be able to:
1.2.1 Serial and parallel data transmission
•
show understanding of what is meant by transmission of data
•
distinguish between serial and parallel data transmission
•
show understanding of the reasons for choosing serial or parallel data transmission
•
show understanding of the need to check for errors
•
explain how parity bits are used for error detection
•
identify current uses of serial and parallel data transmission, such as Integrated Circuits (IC) and
Universal Serial Bus (USB)
1.2.2 Security aspects
•
show understanding of the security aspects of using the Internet and understand what methods
are available to help minimise the risks
•
show understanding of the Internet risks associated with malware, including viruses, spyware and
hacking
•
explain how anti-virus and other protection software helps to protect the user from security risks
(this also links into section 1.4 of the syllabus)
1.2.3 Internet principles of operation
10
•
show understanding of the role of the browser and Internet server
•
show understanding of what is meant by hypertext transfer protocol (http) and HTML
•
distinguish between HTML structure and presentation
•
show understanding of the concept of MAC address, Internet Protocol (IP) address and cookies
M.Mushtaq
Cambridge O Level Computer Science 2210. Syllabus
for examination in 2015.
03215275281
Syllabus content
5
1.3
Hardware and software
Candidates should be able to:
1.3.1 Logic gates
•
use logic gates to create electronic circuits
•
understand and define the functions of NOT, AND, OR, NAND, NOR and XOR (EOR) gates,
including the binary output produced from all the possible binary inputs (all gates, except the NOT
gate, will have 2 inputs only)
•
draw truth tables and recognise a logic gate from its truth table
•
recognise and use the following standard symbols used to represent logic gates:
•
produce truth tables for given logic circuits, for example:
NOT
AND
OR
a
0
0
0
0
1
1
1
1
•
NAND
b
0
0
1
1
0
0
1
1
c
0
1
0
1
0
1
0
1
NOR
XOR
out
produce a logic circuit to solve a given problem or to implement a given written logic statement,
such as IF (switch A is NOT on) OR (switch B is on AND switch C is NOT on) then alarm, X,
sounds
1.3.2 Computer architecture and the fetch-execute cycle
•
show understanding of the basic Von Neumann model for a computer system and the stored
program concept (program instructions and data are stored in main memory and instructions are
fetched and executed one after another)
•
describe the stages of the fetch-execute cycle
1.3.3 Input devices
•
describe the principles of operation (how each device works) of a range of input devices
including 2D and 3D scanners, barcode readers, digital cameras, keyboards, mice, touch screens,
microphones
•
describe how these principles are applied to real-life scenarios, for example: scanning of
passports at airports, barcode readers at supermarket checkouts, and touch screens on mobile
devices
•
describe how a range of sensors can be used to input data into a computer system, including
light, temperature, magnetic field, gas, pressure, moisture, humidity, pH/acidity/alkalinity and
motion/infra-red
•
describe how these sensors are used in real-life scenarios, for example: street lights, security
devices, pollution control, games, and household and industrial applications
M.Mushtaq
Cambridge O Level
Computer Science 2210. Syllabus for03215275281
examination in 2015.
11
Syllabus content
6
1.3.4 Output devices
•
describe the principles of operation of a range of output devices, including: inkjet, laser and 3D
printers; 2D and 3D cutters; speakers and headphones; actuators; flat-panel display screens,
including Liquid Crystal Display (LCD) and Light-Emitting Diodes (LED); and LCD projectors and
Digital Light Projectors (DLP)
•
describe how these principles are applied to real-life scenarios for example: printing single items
on demand or in large volumes; banks of digital displays; use of small screens on mobile devices;
smart boards
1.3.5 Memory, storage devices and media
•
show understanding of the difference between: primary, secondary and off-line storage and
provide examples of each, such as, primary: Read Only Memory (ROM), Random Access Memory
(RAM) and DVD-RAM; secondary: hard disk drive (HDD) and Solid State Drives (SSDs); off-line:
Digital Versatile Disks (DVDs), Compact Disks (CDs), Blu-ray, USB flash memory and removable
disks
•
describe the principles of operation of a range of types of storage devices and media including
magnetic, optical and solid state
•
describe how these principles are applied to currently available storage solutions, such as SSDs,
hard disk drives, USB flash memory, DVDs, CDs and Blu-ray
•
calculate the storage requirement of a file
1.3.6 Operating systems
•
describe the purpose of an operating system
•
show understanding of the need for interrupts
1.3.7 High- and low-level languages and their translators
12
•
show understanding of the need for both high-level and low-level languages
•
show understanding of the need for compilers when translating programs written in a high-level
language
•
show understanding of the use of interpreters with high-level language programs
•
show understanding of the need for assemblers when translating programs written in assembly
language
M.Mushtaq
Cambridge O Level Computer Science 2210. Syllabus
for examination in 2015.
03215275281
7
1.4
Syllabus content
Security
Candidates should be able to:
1.4.1
•
show understanding of the need to keep data safe from accidental damage, including corruption
and human errors
•
show understanding of the need to keep data safe from malicious actions, including unauthorised
viewing, deleting, copying and corruption
1.4.2
•
show understanding of how data are kept safe when stored and transmitted, including:
○
use of passwords, both entered at a keyboard and biometric
○
use of firewalls, both software and hardware, including proxy servers
○
use of Secure Socket Layer (SSL)
○
use of symmetric encryption (plain text, cypher text and use of a key) showing understanding
that increasing the length of a key increases the strength of the encryption
1.4.3
•
show understanding of the need to keep online systems safe from attacks including denial of
service attacks, phishing, pharming
1.4.4
•
1.5
describe how the knowledge from 1.4.1, 1.4.2 and 1.4.3 can be applied to real-life scenarios
including, for example, online banking, shopping
Ethics
Candidates should be able to:
•
show understanding of computer ethics, including copyright issues and plagiarism
•
distinguish between free software, freeware and shareware
•
show understanding of the ethical issues raised by the spread of electronic communication and
computer systems, including hacking, cracking and production of malware
M.Mushtaq
Cambridge O Level
Computer Science 2210. Syllabus for03215275281
examination in 2015.
13
Syllabus content
8
Section 2 Practical Problem-solving and Programming
2.1
Algorithm design and problem-solving
Candidates should be able to:
2.1.1 Problem-solving and design
•
show understanding that every computer system is made up of sub-systems, which in turn are
made up of further sub-systems
•
use top-down design, structure diagrams, flowcharts, pseudocode, library routines and subroutines
•
work out the purpose of a given algorithm
•
explain standard methods of solution
•
suggest and apply suitable test data
•
understand the need for validation and verification checks to be made on input data (validation
could include range checks, length checks, type checks and check digits)
•
use trace tables to find the value of variables at each step in an algorithm
•
identify errors in given algorithms and suggest ways of removing these errors
•
produce an algorithm for a given problem (either in the form of pseudocode or flowchart)
•
comment on the effectiveness of a given solution
2.1.2 Pseudocode
•
understand and use pseudocode for assignment, using ←
•
understand and use pseudocode, using the following conditional statements:
IF … THEN … ELSE … ENDIF
CASE … OF … OTHERWISE … ENDCASE
•
understand and use pseudocode, using the following loop structures:
FOR … TO … NEXT
REPEAT … UNTIL
WHILE … DO … ENDWHILE
•
understand and use pseudocode, using the following commands and statements:
INPUT and OUTPUT (e.g. READ and PRINT)
totalling (e.g. Sum ← Sum + Number)
counting (e.g. Count ← Count + 1)
(Candidates are advised to try out solutions to a variety of different problems on a computer using a
language of their choice; no particular programming language will be assumed in this syllabus.)
14
M.Mushtaq
Cambridge O Level Computer Science 2210. Syllabus
for examination in 2015.
03215275281
9
2.2
Syllabus content
Programming
Candidates should be able to:
2.2.1 Programming concepts
•
declare and use variables and constants
•
understand and use basic data types: Integer, Real, Char, String and Boolean
•
understand and use the concepts of sequence, selection, repetition, totalling and counting
•
use predefined procedures/functions
2.2.2 Data structures; arrays
•
declare the size of one-dimensional arrays, for example: A[1:n]
•
show understanding of the use of a variable as an index in an array
•
read values into an array using a FOR … TO … NEXT loop
2.3
Databases
Candidates should be able to:
•
define a single-table database from given data storage requirements
•
choose a suitable primary key for a database table
•
perform a query-by-example from given search criteria
M.Mushtaq
Cambridge O Level
Computer Science 2210. Syllabus for03215275281
examination in 2015.
15
.
10
4
14 Study the flowchart very carefully.
For
Examiner's
Use
START
T=1
INPUT N
A
X=1
T=T*X
X=X+1
B
No
Is X =
N + 1?
Yes
STOP
OUTPUT T
(a) Complete the table to show what outputs you would expect for the two inputs.
Input N
5
1
Output T
[2]
(b) Write down a possible LOOP construct for the section A to B in the flowchart using
pseudocode.
[2]
© UCLES 2009
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M.Mushtaq
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5
15 Aeroplanes use on-board computer power to allow them to operate more efficiently and
safely.
For
Examiner's
Use
(a) How is data during a flight collected and fed back to on-board computers?
[2]
(b) Why are computer systems thought to be safer than human pilots?
[2]
(c) However, pilots are still used on all flights. Why is this?
[2]
(d) What recent developments have led to more use of computer control in newly designed
aeroplanes?
[1]
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6
(e) Describe how the computer would know when to make course corrections during a
flight.
[2]
(f) At the airport, baggage check-ins use bar codes which are read by computers.
(i) What information would be stored on the bar code?
[1]
(ii) Why do airports use the bar codes on baggage?
[1]
© UCLES 2009
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M.Mushtaq
03215275281
For
Examiner's
Use
.
13
7
16 The following flowchart shows what happens when a customer uses a credit card to pay for
goods at a supermarket. Ten of the boxes are blank.
Using the items from the list, insert the ten missing statements using the appropriate
number only. Each statement may be used once only.
For
Examiner's
Use
START
Insert credit card
Type in PIN
STOP
No
Yes
LIST OF STATEMENTS
Yes
No
Yes
No
1
2
3
4
5
6
7
8
9
10
are PIN details correct?
are there sufficient funds?
card removed
end transaction
is expiry date exceeded?
is card reported stolen?
money transfer takes place
print itemised bill
read credit card details
two computers communicate
No
Yes
STOP
[5]
© UCLES 2009
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8
17 A car sales company uses a database.
For
Examiner's
Use
Here are three tables from the database:
New Car Sales
Customer
Reference
151319
162154
171216
Car Ordered
Specification
Delivery Date
Cancelled order
VW Golf
BMW 320i
None
21215168
07981624
Not applicable
December 2008
February 2009
Customer Name
Customer Address
Trade In?
J Smith
M Kyle
D Khan
S Gogic
D Marques
7 Toll Road
14 Coast Road
19 Main Street
555 Trabant Road
21 Lakki Harbour
No
No
Yes
No
Yes
Car Description
BMW 320i
VW Golf
VW Golf
Ford Focus
List of Extras
CNORVZ
ABCETU
BDEFJL
APRSW
Cost Price ($)
48 500
16 200
21 000
17 000
Customer Details
Customer
Reference
141516
151319
162154
165196
171216
Car Manufacturer
Specification
07981624
21151198
21215168
31311115
(a) How many records are shown in the Customer Details table?
[1]
(b) (i) Which field connects the New Car Sales table with the Customer Details table?
[1]
(ii) Which field connects the New Car Sales table with the Car Manufacturer table?
[1]
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(c) Give two reasons why List of Extras in the Car Manufacturer table is stored in code
form.
For
Examiner's
Use
1
2
[2]
(d) A customer goes into the showroom and the salesperson keys in 162154. What fields
and information would be shown on the output screen?
[2]
(e) Give one advantage to the car sales company of holding customer information on a
database.
[1]
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0
18 A small airport handles 400 flights per day from three airlines:
FASTAIR
SWIFTJET
KNIGHTAIR
For
Examiner's
Use
(code FA)
(code SJ)
(code KA)
Each flight is identified by the airline code and 3 digits. For example FA 156.
Write an algorithm, using pseudocode or otherwise, which monitors the 400 flights into and
out of the airport each day. The following inputs, processing and outputs are all part of the
monitoring process:
•
•
•
•
input flight identification
calculate number of flights per day for each of the three airlines
output the percentage of the total flights per day by each airline
any validation checks must be included
[5]
Permission to reproduce items where third party owned material protected by copyright is included has been sought and cleared where possible. Every
reasonable effort has been made by the publisher (UCLES) to trace copyright holders, but if any items requiring clearance have unwittingly been included, the
publisher will be pleased to make amends at the earliest possible opportunity.
University of Cambridge International Examinations is part of the Cambridge Assessment Group. Cambridge Assessment is the brand name of University of
Cambridge Local Examinations Syndicate (UCLES), which is itself a department of the University of Cambridge.
© UCLES 2009
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Mark Scheme: Teacher version
GCE O Level – May/June 2009
Page 9
Syllabus
7010
Paper
01
(ii) any one from:
tracking/uniquely identifies baggage/ensures baggage gets to right place
increased security
links to passenger/ensures luggage cannot travel without passenger
[1]
16
START
Insert credit card
Type in PIN
STOP
No
1
4
(1 mark)
Yes
9
(1 mark)
10
Yes
5/6
(1 mark)
No
Yes
6/5
No
No
2
(1 mark)
Yes
7
3
(1 mark)
8
STOP
[5]
© UCLES 2009
M.Mushtaq
03215275281
Page 10
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18
Mark Scheme: Teacher version
GCE O Level – May/June 2009
Syllabus
7010
Paper
01
17 (a) 5
[1]
(b) (i) Customer Reference
(ii) Specification
[2]
(c) any two from:
reduces typing errors
uses less memory
faster to type in
quicker to sort
store in one field
easier to validate
[2]
(d) Car Description/Car Ordered
Delivery Date
Specification
Customer Name
Customer Address
Trade In
VW Golf }
Dec 2008 } New Car Sales
21215168 }
D Khan
19 Main Street
Yes
}
} Customer Details
}
(1 mark 1 field name and contents from New Car Sales table plus 1 field name and
contents from Customer Details table)
List of Extras
Cost Price ($)
BDEFJL }
21 000
} Car Manufacturer
(1 mark 1 field name and contents from Car Manufacturer table)
[2]
(e) any one advantage from:
later use if customer wants to trade in again in 2 or 3 years’ time
can send out new product information
if safety/recall issues from car manufacturers
service/safety check reminders
[1]
18 marking points (1 mark per item up to the maximum of 5):
initialise fa, sj and ka to zero
correct loop
inputs (in correct place)
addition of number of flights per airline
any validation checks carried out
calculate percentages
outputs (in correct place and ONLY if some evidence of any attempt at processing)
© UCLES 2009
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Mark Scheme: Teacher version
GCE O Level – May/June 2009
Page 11
Syllabus
7010
Paper
01
sample program/algorithm
fa = 0; sj = 0; ka =0;
} 1 mark
for x = 1 to 400
} 1 mark
input lettercode
}
} 1 mark
}
input numbercode
if lettercode = “FA” then fa = fa + 1
if lettercode = “KA” then ka = ka + 1
}
}
} 1 mark
}
}
else print “error”
} 1 mark
if lettercode = “SJ” then sj = sj + 1
next x
fapercent = fa/4
kapercent = ka/4
}
}
} 1 mark
}
}
print fapercent, sjpercent, kapercent
} 1 mark
sjpercent = sj/4
© UCLES 2009
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[5]
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Mark Scheme: Teacher version
GCE O Level – May/June 2009
Page 12
Syllabus
7010
Paper
01
Sample flowchart:
START
fa = sj = ka = 0 x = 1
Input lettercode
Input numcode
Yes
Is lettercode = FA
fa = fa+1
No
Yes
sj = sj+1
Is lettercode = SJ
No
Yes
Is lettercode = KA
ka = ka+1
No
Output “error”
Stop
x=x+1
Yes
No
Is x<=400
fapercent = fa/4
sjpercent = sj/4
kapercent = ka/4
Ouput fapercent,
sjpercent, kapercent
© UCLES 2009
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21
9
Study the flowchart.
For
Examiner's
Use
START
C=1
INPUT N
N = N/10
Is
N < 1?
Yes
OUTPUT C
STOP
No
C=C+1
Complete the table to show what outputs you would expect for the three inputs.
INPUT N
OUTPUT C
55
2100
1
[3]
© UCLES 2009
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10 Houses for sale can be viewed using a Virtual Reality Tour. This takes you round the house
in three dimensions (3D) on a computer screen “as if you were there in person”.
For
Examiner's
Use
(a) Give two advantages of Virtual Reality Tours.
1
2
[2]
(b) How are the house images created for the Virtual Reality Tour?
[2]
(c) What two changes in technology have allowed Virtual Reality Tours to become
possible?
1
2
[2]
(d) Describe a typical tool on a Virtual Reality Tour web page.
[1]
(e) Give another application of Virtual Reality Tours.
[1]
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0
11 A spreadsheet has been set up to store results of football matches for 12 teams. Halfway
through the year the results were:
A
1
2
Team
Name
B
C
Won
Drawn
(3 points) (1 point)
D
E
F
G
Lost
(0 points)
Number
of Points
Goals
For
Goals
Against
H
I
Goal
Matches
Difference Played
3
4
United
7
2
2
23
16
4
12
11
5
City
7
2
2
23
21
10
11
11
6
Town
6
1
4
19
16
10
6
11
7
Academics
4
6
1
18
12
9
3
11
8
Rovers
4
4
3
16
16
14
2
11
9
Runaways
3
5
3
14
10
12
-2
11
10
Yorkers
3
5
3
14
10
14
-4
11
11
Albion
3
3
5
12
14
15
-1
11
12
Knights
4
0
7
12
10
18
-8
11
13
Sporting
2
5
4
11
10
12
-2
11
14
Nohopers
2
3
6
9
8
16
-8
11
15
Jokers
2
2
7
8
6
14
-8
11
(a) What formula is in cell E4 to calculate the Number of Points for United?
[1]
(b) Goal Difference = (Goals For – Goals Against). What formula is in cell H4 to find Goal
Difference for United?
[1]
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For
Examiner's
Use
.
24
(c) State two ways of checking the correctness of data in columns F and G.
For
Examiner's
Use
1
2
[2]
(d) Rovers played Yorkers and won 2 – 0. Columns B, D, F, G and I were updated. Which
other cells would be automatically updated?
[2]
© UCLES 2009
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4
13 A radio station keeps a database of all its music CDs. Here is part of this database:
Reference
CD title
Number
1111
Afternoon Glory
number of
tracks
12
special
edition
N
CD length
(mins)
55
number of
hit tracks
1
1112
Stone Tulips
10
N
42
3
1113
Aftermath
8
N
33
0
1114
Major Peppers
15
Y
72
5
1115
Seaside
9
N
40
2
1116
Lookout
12
N
62
2
1117
Future Dreams
11
N
60
3
1118
Moonlight
14
Y
70
2
(a) How many records are there in the database section?
[1]
(b) If the following query was input:
(CD length (mins) < 60) AND (number of hit tracks > 1)
using Reference Number only, write down which data items would be output.
[1]
(c) Write down a query to select which CDs are special edition or have more than
10 tracks.
[2]
(d) The database is sorted in descending order on CD length (mins). Using Reference
Number only, write down the order of the records following this sort.
[1]
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9
17 (a) A car’s speed is measured between points A and B, which are 200 km apart.
A
For
Examiner's
Use
B
200 km
The final speed of the car is calculated using the formula:
200
Final Speed = ────────
Time (hours)
What is the final speed of a car if it takes 2 hours to get from A to B?
[1]
Part (b) is on the next page.
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0
(b) Write an algorithm, using pseudocode or otherwise, which inputs the times for 500
cars, calculates the final speed of each car using the formula in part (a), and then
outputs:
•
•
•
•
For
Examiner's
Use
the final speed for ALL 500 cars
the slowest (lowest) final speed
the fastest (highest) final speed
the average final speed for all the cars.
[6]
Permission to reproduce items where third party owned material protected by copyright is included has been sought and cleared where possible. Every
reasonable effort has been made by the publisher (UCLES) to trace copyright holders, but if any items requiring clearance have unwittingly been included, the
publisher will be pleased to make amends at the earliest possible opportunity.
University of Cambridge International Examinations is part of the Cambridge Assessment Group. Cambridge Assessment is the brand name of University of
Cambridge Local Examinations Syndicate (UCLES), which is itself a department of the University of Cambridge.
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Mark Scheme: Teach s’ version
GSE O LEVEL – October/November 2009
Syllabus
7010
Paper
01
(e) Any one from: e.g.
inside chemical plants
inside nuclear plants/reactors
hotels
games
training
interactive mapping
museums
[1]
11 (a) (E4) (=) B4 * 3 + C4
(B4*3 + C4*1 + D4*0 also correct)
[1]
(b) (H4) (=) F4 – G4
[1]
(c) Any two from:
validation checks
(d)
- no negative numbers
- whole numbers only
- no letters/type check
- range check
check if sum of numbers in column G = sum of numbers in column F
check if the sum of the numbers in column H = 0
[2]
E8, H8,
E10, H10
← 1 mark → ← 1 mark →
columns E and H (1 mark only)
[2]
12 (a) Any one from:
infra-red sensors (to detect movement)
ADC (in case sensors are analogue)
[1]
(b) Any one from:
need analogue signal to operate camera motors to move lens/camera
computer output is digital
[1]
(c) Any one from:
movement detected
computer compares new image with last image
images are stored and played back later
[1]
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Mark Scheme: Teach s’ version
GSE O LEVEL – October/November 2009
Page 8
Syllabus
7010
Paper
01
(d) Any two from:
no film processing to be done/doesn’t run out of film/cost of buying film
instantaneous checks
camera won’t need manual emptying
[2]
(e) (i) 400/0.4 = 1000 images
alternative answer 400/0.0004 = 1 000 000 images approx
(1 048 576 exactly)
[1]
(ii) store images on another hard drive or on DVD/CDs
archive old images
[1]
13 (a) 8
[1]
(b) 1112, 1115
(c) (special edition = “Y“)
< ─ ─ ─1 mark ─ ─ ─>
(number of tracks > 10)
< ─ ─ ─1 mark ─ ─ ─>
[1]
OR
(number of tracks > 10)
< ─ ─ ─ ─1 mark ─ ─ ─ ─>
OR
(special edition = “Y“)
< ─ ─ ─ ─1 mark ─ ─ ─ ─>
[2]
(d) 1114, 1118, 1116, 1117, 1111, 1112, 1115, 1113
[1]
(e) (i) Any one from:
(auto capture) on the database itself
transaction file
spreadsheet
[1]
(ii) link through the reference number/CD title/primary key
[1]
14 Any four points from:
get information from experts
input data into knowledge base
create rules base
create inference engine
create human-machine interface/question and answer sessions
firstly test system with “known” problems and solutions
create output system screen/format
create/design validation routines
[4]
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15 (a) TAB:
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Mark Scheme: Teach s’ version
GSE O LEVEL – October/November 2009
Syllabus
7010
Paper
01
011101
FRET: 0 1 0 0 1 0
[2]
(b) (i)
[1]
(ii) 19
[1]
(c) Any two from:
can store music directly onto digital, optical media/mp3 players
easy to modify music by simply changing binary values
easy to teach somebody how to play an instrument
easy to convert music for other instruments
allows auto play back through interfaces
uses less memory
[2]
16 (a) Any two from:
eliminates ticket fraud
can’t get lost (in the post)/sent to wrong address
easier to amend flight details (no tickets to re-print)
reduces booking expenses
faster processing
can check-in from anywhere (therefore saving queuing time at airport)
[2]
(b) Any two from:
computer crashes (therefore “disappearing reservation” – in such cases, paper tickets are
better)
e-tickets not “portable” between airlines whereas paper tickets are
human confidence – prefer to have “proof” of booking with paper ticket
[2]
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Mark Scheme: Teach s’ version
GSE O LEVEL – October/November 2009
Syllabus
7010
Paper
01
(c) Any two from e.g.
destination airport
starting airport
name(s) of passenger(s)
passport number/nationality
special requirements
number of passengers
dates/times of flights
cost of tickets
full flight itinerary
special offers
information about the airlines
information about flight facilities
sort on cheapest/fastest routes/flights
ability to check availability of flights/search for flights
terms and conditions
[2]
17 (a) 100 (km/hr)
[1]
(b) Marking points
Initialisation (slowest = 1000 or an equivalent high value)
Correct loops structure and control
Input (in correct place)
Calculation of final speed using given formula in part (a) inside the loop
Output the final speed for ALL cars inside the loop
Calculation highest speed input
Calculation slowest speed input
Calculate the average (two parts to this calculation)
Final outputs (correct place + some form of processing done)
[6]
Sample program:
total = 0
highest = 0
slowest = 1000
for n = 1 to 500
input time
finalspeed = 200/time
print finalspeed
total = total + finalspeed
if finalspeed > highest
then highest = finalspeed
if finalspeed < slowest
then slowest = finalspeed
next n
average = total/500
print average, highest, slowest
}
} 1 mark
}
} 1 mark
} 1 mark
} 1 mark
} 1 mark
}
} 1 mark
}
} 1 mark
} 1 mark
} 1 mark
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UNIVERSITY OF CAMBRIDGE INTERNATIONAL EXAMINATIONS
General Certificate of Education Ordinary Level
*8454621681*
7010/11
COMPUTER STUDIES
May/June 2010
Paper 1
2 hours 30 minutes
Candidates answer on the Question Paper.
No Additional Materials are required.
READ THESE INSTRUCTIONS FIRST
Write your Centre number, candidate number and name on all the work you hand in.
Write in dark blue or black pen.
You may use a soft pencil for any diagrams, graphs or rough working.
Do not use staples, paper clips, highlighters, glue or correction fluid.
DO NOT WRITE IN ANY BARCODES.
Answer all questions.
No marks will be awarded for using brand names of software packages or hardware.
At the end of the examination, fasten all your work securely together.
The number of marks is given in brackets [ ] at the end of each question or part question.
For Examiner's Use
This document consists of 17 printed pages and 3 blank pages.
IB10 06_7010_11/FP
© UCLES 2010
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1
Explain, with examples, the following five computer terms:
For
Examiner's
Use
(a) Video conferencing
[2]
(b) Simulation
[2]
(c) Interrupt
[2]
(d) Batch processing
[2]
(e) Expert system
[2]
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3
You have been asked to produce a presentation on the social impact of computers on shop
workers.
(a) What software features would you use to make your presentation interesting?
[2]
(b) What could you include in your presentation to show how the workers would be
affected?
[2]
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4
A company is concerned about three aspects of the security of data stored in computer files:
•
•
•
data corruption
data loss
illegal access to data
For each of the above, give one reason why it could occur and state one method of
prevention. Your reasons must be different in each case.
Data corruption
Reason:
Data corruption
Prevention:
Data loss
Reason:
Data loss
Prevention:
Illegal access to data
Reason:
Illegal access to data
Prevention:
[6]
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Examiner's
Use
.
36
6
(a) Give three different types of device that allow human beings to interface with computer
systems.
1
2
3
[3]
(b) Give three automatic data capture devices and give a suitable application for each
device.
Device 1
Application 1
Device 2
Application 2
Device 3
Application 3
[6]
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Examiner's
Use
.
37
7
Describe how a supermarket would use computer technology to carry out automatic stock
control.
For
Examiner's
Use
[3]
8
(a) Describe the term virtual reality. Include examples of the special hardware needed to
react with virtual reality systems in your answer.
[3]
(b) Give two advantages of using virtual reality systems.
1
2
[2]
(c) Give one example of an application that uses virtual reality.
[1]
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9
Many software applications use drop-down menus.
For
Examiner's
Use
(a) What is meant by the term drop-down menu?
[2]
(b) A user is filling out an order form on the Internet.
(i) Give one example where a drop-down menu could help the user.
(ii) Give one example where a drop-down menu should not be used to help the user.
[2]
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10 (a) Compilers and interpreters translate high-level languages. Give two differences
between compilers and interpreters.
For
Examiner's
Use
1
2
[2]
(b) Programs can be written using high-level or low-level languages.
Give one advantage of using each method.
High-level language advantage
Low-level language advantage
[2]
(c) What is meant by top-down design when developing new software?
[1]
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0
11 A student set up a spreadsheet to compare share prices in six companies over five years.
1
2
3
4
5
6
7
8
A
B
C
Name of
company
Year:
Global Oil
GSD
KLN
Nesto
Takkco
Uniway
Share
price
2005
Share
Share
Share
Share
price
price
price
price
2006
2007
2008
2009
190
305
130
140
722
622
325
324
71
71
63
45
418
522
600
640
316
394
202
122
135
254
365
570
81
619
60
316
149
122
D
E
F
G
Average
share
price
169
522
62
499
237
289
H
Highest
share
price
305
722
71
640
394
570
(a) What formula is in cell G5 to find the average (mean) share price for KLN?
[1]
(b) What formula is in cell H5 to find the highest share price for KLN?
[1]
(c) If the data in cell E4 was changed to 425, which cells would be automatically updated?
[1]
(d) The student wants to extend the spreadsheet to include share prices for 2010.
Describe how the student would do this.
[2]
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41
12 A golf course charges $10 for each game of two people. Each additional person incurs a
further charge of $2 per game. If they book two or more games in advance, they get a 10%
discount on the total charge.
For
Examiner's
Use
The following program has been written in pseudocode to calculate the charges for a game.
1
2
3
4
5
6
7
8
extracost = 0
input numberpeople, numbergames
charge = 10 * numbergames
extrapeople = numberpeople – 2
if numberpeople < 2 then extracost = 2 * extrapeople * numbergames
charge = extracost
if numbergames > 1 then charge = charge * 0.1
print charge
There are three errors in the program. Locate these errors and suggest a correct piece of
coding.
Error 1
Correction 1
Error 2
Correction 2
Error 3
Correction 3
[6]
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2
13 Networks can have ring, bus or star topology.
For
Examiner's
Use
(a) Draw and name a diagram to show two of these networks.
Network 2
Network 1
Name: …………………………….
Name: …………………………….
[2]
(b) Give one advantage of each chosen network.
Advantage network 1
Advantage network 2
[2]
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3
14 A shower unit is controlled by sensors and a microprocessor.
For
Examiner's
Use
cold water in
water valve
water heater
sensors
microprocessor
hot water out
(a) Describe how the sensors and microprocessor are used to ensure the correct water
flow and water temperature are maintained.
[4]
(b) Give one safety feature that could be built into the shower unit in case the sensors
and/or microprocessor fail.
[1]
(c) What is the advantage of having microprocessor control rather than manual control of
water flow and temperature?
[1]
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4
15 A database has been set up to bring together information about the world’s tallest buildings.
A section of the database is shown below.
Ref
No.
TA1
MA1
US1
CH1
CH2
CH3
CH4
US2
CH5
CH6
DU1
TA2
Building Name
City
Country
Year
Taipei 101
Petronas Towers
Sears Tower
Jiu Mao Building
Finance Centre
CITIC Plaza
Shun Hing Square
Empire State Building
Central Plaza
Bank of China
Emirates Tower
Tuntex Sky Tower
Taipei
Kuala Lumpur
Chicago
Shanghai
Hong Kong
Guangzhan
Shenzhen
New York
Hong Kong
Hong Kong
Dubai
Kaohsiung
Taiwan
Malaysia
USA
China
China
China
China
USA
China
China
Dubai
Taiwan
2004
1998
1974
1999
2003
1996
1996
1931
1992
1989
1999
1997
No. of
Floors
101
88
110
88
88
80
69
102
78
70
54
85
Height
(m)
508
452
442
421
415
391
384
381
374
367
355
348
Height
(ft)
1667
1483
1451
1381
1362
1283
1260
1250
1227
1205
1165
1140
(a) How many records are in the section of the database shown?
[1]
(b) Using Ref No. only, which records would be output if the following search condition was
entered:
(Year < 1990) AND (Height (m) > 375)?
[1]
(c) Write down a search condition to find out how many buildings are in China or how many
buildings have more than 80 floors.
[2]
(d) For each of the following fields give a different validation check.
Year
Ref No.
[2]
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45
5
(e) The database was sorted in descending order of Year. Using Ref No. only, write down
the results of the sort.
For
Examiner's
Use
[1]
16 A company has set up an Internet website to sell their electrical goods online.
(a) Give two features you would expect to see on the website.
1
2
[2]
(b) Payments for goods can be made by credit/debit cards. Data from the cards is
encrypted.
(i) What is encryption?
(ii) Why is data encrypted?
[2]
(c) Apart from credit card fraud, people have other fears about buying from the Internet.
Describe one of these fears.
[1]
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6
17 (a) Two methods of connecting to the Internet are dial-up and broadband.
For
Examiner's
Use
Give two advantages of using broadband.
1
2
[2]
(b) Computers often use wireless (WiFi) technology to connect to the Internet. Give one
advantage and one disadvantage of using WiFi.
Advantage
Disadvantage
[2]
(c) Apart from computers, name another device that uses WiFi technology.
[1]
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7
18 A group of students were monitoring the temperature every day over a one-year period.
Readings were taken ten times every day (you may assume a year contains 365 days).
Write an algorithm, using pseudocode or flowchart, which
•
•
•
•
•
inputs all the temperatures (ten per day)
outputs the highest temperature taken over the year
outputs the lowest temperature taken over the year
outputs the average temperature per day
outputs the average temperature for the whole year
[7]
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Examiner's
Use
.
48
UNIVERSITY OF CAMBRIDGE INTERNATIONAL EXAMINATIONS
GCE Ordinary Level
MARK SCHEME for the May/June 2010 question paper
for the guidance of teachers
7010 COMPUTER STUDIES
7010/11
Paper 11, maximum raw mark 100
This mark scheme is published as an aid to teachers and candidates, to indicate the requirements of
the examination. It shows the basis on which Examiners were instructed to award marks. It does not
indicate the details of the discussions that took place at an Examiners’ meeting before marking began,
which would have considered the acceptability of alternative answers.
Mark schemes must be read in conjunction with the question papers and the report on the
examination.
•
CIE will not enter into discussions or correspondence in connection with these mark schemes.
CIE is publishing the mark schemes for the May/June 2010 question papers for most IGCSE, GCE
Advanced Level and Advanced Subsidiary Level syllabuses and some Ordinary Level syllabuses.
M.Mushtaq
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Mark Scheme: Teacher version
GCE O LEVEL – May/June 2010
Syllabus
7010
Paper
11
(a) video conferencing
Any two points from:
– meeting between 2 or more participants
– using computer networks/Internet
– to transmit audio/video data in real time
– pictures appear in a window on a monitor in real time
– reference to hardware (webcams, speakers, microphones)
– reference to software (communications, compression)
[2]
(b) simulation
Any two points from:
– studying the behaviour of a system
– by using a model/mathematical representation
– results can be predicted
– e.g. flight (or other) simulator, modelling hazardous chemical processes
– e.g. 10-pin bowling computer game
[2]
(c) interrupt
Any two points from:
– a signal/request generated by a device/program
– which causes a break in the execution of a program/stops the program
– e.g. printer out of paper, <BREAK> key pressed, disk full
[2]
(d) batch processing
Any two points from:
– processing doesn’t start until all data is collected
– JCL (any reference to Job Control Language)
– no need for user interaction
– processed all in one go
– done at “quiet” times
– output not time sensitive
– e.g. billing, payroll, cheque processing
[2]
(e) expert system
Any two points from:
– computer system that emulates/simulates human knowledge/contains knowledge of
human expert
– uses an inference engine
– contains a knowledge base
– made up of rule base
– reference to expert system shell
– outputs probability of diagnosis given being correct/produces reasoned conclusions
– uses “Yes/No”, multichoice interface
– e.g. medical diagnosis, chess, prospecting, financial modelling, diagnostics
[2]
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3
4
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50
Mark Scheme: Teacher version
GCE O LEVEL – May/June 2010
Syllabus
7010
Paper
11
Any two tasks from:
– design data collection forms
– design input forms/user interface
– design systems flowcharts
– design output forms/reports/screens
– design/select validation rules
– design/select verification methods
– design test plan/strategy
– specify/select hardware
– specify/select software
– design algorithms/program flowcharts/pseudocode
– specify data structures
– design files (structures)/tables / layout
– design queries
[2]
(a) Any two features from:
– sound and/or video clips embedded in the presentation/multimedia
– animation effects
– diagrams/graphs/charts (in colour)/colour/text fonts etc
– hyperlinks
[2]
(b) Any two from:
– how it affects tasks such as filing/ordering etc.
– retraining aspects
– deskilling aspects
– unemployment
[2]
Any three different reasons and associated preventions
(prevention must match reason):
1 mark for reason, 1 mark for prevention
award each point only once
data corruption and data loss
viruses -use anti virus software, firewalls, no Internet access
power loss
–
back-ups, UPS
malicious damage
–
back-ups, password protection, controlled access
computer crash
–
back-ups, parallel computer (systems)
damage to CDs/disks
–
back-ups
operator error
–
training / good user interfaces
illegal access
hacking/unauthorised access
–
computer left logged on
–
passwords, log-in ids, anti-hacking software
(physical) lock room/computer
log off when not in use, lock computer
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Mark Scheme: Teacher version
GCE O LEVEL – May/June 2010
Page 4
5
Paper
11
1 mark per description, 1 mark per advantage, 1 mark per disadvantage
Direct
– old system stopped and next day new system started
Advantage:
– benefits are immediate/less time wasted
– reduced costs (only one system so fewer staff)
– less likely to malfunction since fully tested
Disadvantage:
– disastrous if new system fails/no fall back option
Parallel
– old system and new system are run together for a time
Advantage:
– if new system goes down, have old system as back up
– can gradually train staff/have time to get used to new system
Disadvantage:
– more expensive/time consuming since 2 systems run together
Pilot
– new system introduced into only part of the company
Advantage:
– if new system fails, only that part affected (rest is alright)
– can gradually train staff/have time to get used to new system
Disadvantage:
– time consuming (waiting to see how new system works)
Phased
6
Syllabus
7010
–
part of the new system introduced and when it proves to work another part is
introduced, etc./introduced part by part
Advantage:
– only a small part of the operations is affected if new system fails
– no need to pay two sets of wages (so cheaper)
– can ensure system works properly before expanding
Disadvantage:
– time consuming (each part needs to be tested before expanding)
[6]
(a) Any three from:
–
–
–
–
–
–
keyboard (type in the responses)
touch screen (select options from on screen menus)
mouse/trackerball/touchpad (click on options from a menu)
microphone (speak options)
data gloves/goggles
camera
[3]
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Mark Scheme: Teacher version
GCE O LEVEL – May/June 2010
Page 5
Syllabus
7010
Paper
11
(b) Any three different devices + associated application areas, e.g.:
7
8
–
bar code reader
–
OMR/mark sensing
–
touch screens
–
sensors
–
cameras
–
MICR
–
microphones
–
magnetic stripe reader
–
data loggers
–
OCR
Scanner
–
–
–
–
–
–
–
–
–
–
–
–
–
–
–
–
–
–
–
–
stock control
library systems
multi-choice papers
questionnaires
information desks/kiosks
choosing goods on line
monitoring chemical plant
central heating systems
traffic control
security
reading bank cheques
reading travellers cheques
telephone systems
games
reading credit cards
reading security cards
weather monitoring
collecting experimental data
reading in documents
scanning in photos etc.
[6]
Any of the following three stages:
– each time item is bought, bar code scanned (at POS)/use of bar codes
– bar code searched for on database/file
– number in stock reduced by 1
– when stock level < re-order level/minimum level ……
– …… automatic re-ordering carried out
– when new stock arrives, stock levels updated
[3]
(a) Any three from:
– 3D visual world
– created by a computer
– form of computer simulation
– data gloves used
– data goggles/headsets used
– hardware/motors to provide movement
– special suits fitted with sensors
[3]
(b) Any two from:
– safety (e.g. can “view” inside a nuclear reactor)
– feeling of “being there”
– can perform “actual tasks” beforehand (without risk)
– less expensive (IF QUALIFIED!!)
[2]
(c) Any one from e.g.:
– (medical) training
– walk throughs (e.g. virtual tours of a house)
– simulators (e.g. flight)
– 3D arcade games
– investigating problems in nuclear/chemical plants
[1]
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Mark Scheme: Teacher version
GCE O LEVEL – May/June 2010
Page 6
9
Syllabus
7010
Paper
11
(a) Any two points from:
– e.g. choose
by clicking on an arrow
– limited number of options available
– highlights option chosen
– use of pointing device to select an option
(b)
[2]
(i) Any one from:
– used where limited number of options exist
– e.g. names of countries, days of month, date of birth
(ii) Any one from:
– cannot be used where “infinite” number of options exist
– e.g. addresses, people’s names
[2]
10 (a) Any two differences from:
compiler
–
interpreter
–
–
needs to be re-compiled every
time a change is made
code can be executed on its own
–
translates whole code in one go
–
–
translates source code into
object code/machine code
produces error list at end of compilation
–
–
–
translates instructions one
at a time ….
then executes the
instructions immediately
only finds errors as each
instruction executed
easier to edit/debug
[2]
(b) Any one high level advantage and any one low level advantage:
high-level language
–
–
–
–
–
–
fewer instructions
no need to understand registers/computer architecture
instructions nearer to human language/English
not machine specific/portable
easier to debug programs
easier to write programs
low-level language
–
–
–
gain knowledge of how a computer works
more control over how registers (etc.) are accessed
can access registers (etc.) directly
[2]
(c) Any one from:
– program/algorithm broken down into simpler modules/smaller tasks
– each module is further sub-divided until basic elements produced
– allows several programmers to work at same time on the software
– can test each module independently
[1]
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Mark Scheme: Teacher version
GCE O LEVEL – May/June 2010
Page 7
Syllabus
7010
Paper
11
11 (a) = AVERAGE(B5:F5) or
= AVERAGE(B5,C5,D5,E5,F5) or
= SUM(B5:F5)/5 or
= (B5+C5+D5+E5+F5)/5
[1]
(b) = MAX(B5:F5)
or
= MAX(B5,C5,D5,E5,F5)
[1]
(c) G4, (H4)
[1]
(d) –
–
[2]
add column between F and G/insert column before G/insert column after F
change the formula(s) to allow 2010 data to be added
12 1 mark for each error identified + 1 mark for each suggested correction
–
error
line 5: numberpeople < 2 is incorrect
correction:
numberpeople > 2
–
error
line 6: the formula/charge = extracost is incorrect
correction:
charge = extracost + charge
–
error
line 7: discount calculation/charge = charge * 0.1 is incorrect,
correction:
charge = charge * 0.9
[6]
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Mark Scheme: Teacher version
GCE O LEVEL – May/June 2010
Page 8
Syllabus
7010
Paper
11
13 (a) Any two from:
Ring
star
bus
[2]
(b) One mark per advantage given:
Ring
–
–
–
can create much larger networks
faster/better operation under heavy workload
requires less cabling than a STAR network, for example
Star
–
–
–
–
easy to install and wire/expand
no disruptions to network if terminal fails
easy to detect faults in the system
central monitoring and network management possible
Bus
–
–
–
failure of single terminal doesn’t affect entire network
easy to connect a new terminal to the network
requires less cabling, therefore less expensive than others
[2]
14 (a) Any four points from:
– flow sensor / temperature sensor ….
– …… send information / signal / data to microprocessor
– ADC converts data/signal (for microprocessor to understand/process)
– microprocessor compares flow rate/temperature with pre-set values
– sends signal to valve/heater to control flow rate/temp as required
– use of a DAC interface
– use of actuators
– system loops continuously until switched off
[4]
(b) Any one from:
– fail safe/switches off automatically
– temperature automatically sets to cold/switches off the heating
– flow cuts off and temperature sets to cold
(NOT a warning light/buzzer comes on)
[1]
(c) Any one from:
– more accurate control
– safer system
– more energy efficient
[1]
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Mark Scheme: Teacher version
GCE O LEVEL – May/June 2010
Page 9
Syllabus
7010
Paper
11
15 (a) 12
[1]
(b) US1,US2
[1]
(c) (Country = “China”) OR (No. of Floors > 80)
←------1 mark ----→ ←-------- 1 mark --------→
(No. of Floors > 80) OR (Country = “China”)
←------1 mark ----→ ←-------- 1 mark --------→
(d)
[2]
(i) range check, character check, length check
(ii) character check, type check, length check, format check
[2]
{
{
(e) TA1, CH2, CH1, DU1, MA1, TA2, CH3, CH4, CH5, CH6, US1, US2
(any order)
(any order)
[1]
16 (a) Any two from e.g.:
– electronic checkout
– shopping basket
– ability to track status of order on line
– secure buying using credit cards
– “when customer bought X, they also bought Y” facility
– search facilities for items
– recognise customers as soon as they log on
– drop down boxes to choose categories
– sales confirmation by automatic email
– save customer details/customised pages
– online help facility
– hyperlinks to other pages
– ability to bookmark/tag page(s)
(b)
(i)
–
–
(ii)
–
–
[2]
Any one from:
process of changing/scrambling/encoding data into a meaningless form
use of software/algorithms to turn data into a meaningless form
Any one from:
to avoid data being read/understood by hackers/unauthorised people
to protect sensitive data from unauthorised people
(c) Any one from:
– viruses being downloaded from the site
– bogus/fake sites
– “unwanted sites”/porn sites coming up when searching
– unsolicited mail
– “cookies” (etc.) being stored on hard drive (spying software)
– hacking
[1]
[1]
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GCE O LEVEL – May/June 2010
Page 10
Syllabus
7010
Paper
11
17 (a) Any two advantages from:
– always “on”/no need to dial into ISP
– connection rate much higher (e.g. 11000 kbps cf 60 kbps)
– flat monthly rate (dial up charges based on number of hours used)
– can use phone line at same time/line not tied up
– allows other facilities such as VoIP
– download rate is much faster
[2]
(b) Any one advantage and any one disadvantage from:
Advantages
– can use anywhere within range
– no trailing wires
Disadvantages
– range can be limited
– possible interference from electronic devices
– security/tapping into WiFi networks
– (often) slower access speed than wired systems
[2]
(c) Any one from:
e.g.
–
–
–
–
–
–
printers
keyboard
mouse
cameras
mobile phone
GPS
[1]
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Mark Scheme: Teacher version
GCE O LEVEL – May/June 2010
Page 11
Syllabus
7010
Paper
11
18 Marking points (maximum of 7 marks)
–
–
–
–
–
–
–
–
–
–
–
–
–
initialising highest and lowest to reasonable values (must not be zero)
first loop controlling one year (365 days)
re-setting total for each day
second loop controlling readings taken per day
read temperature
calculate total day temperature
calculate total year temperature
identifying highest temperature
identifying lowest temperature
finding average temperature for day
finding average temperature for year
output average day temperature inside loop
output highest, lowest, average outside the loop
Sample algorithm in pseudocode
highest = -100: lowest = 100: total year = 0
} 1 mark
for c = 1 to 365
} 1 mark
total day = 0
} 1 mark
for d = 1 to 10
} 1 mark
read temp
} 1 mark
total day = total day + temp
} mark
total year = total year + temp
} 1 mark
if temp > highest then highest = temp
} 1 mark
if temp < lowest then lowest = temp
} 1 mark
next d
average day = total day/10
} 1 mark
print average day
} 1 mark
next c
average year = total year/3650
} 1 mark
print highest, lowest, average year
} 1 mark
[7]
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UNIVERSITY OF CAMBRIDGE INTERNATIONAL EXAMINATIONS
General Certificate of Education Ordinary Level
*5409191667*
7010/12
COMPUTER STUDIES
May/June 2010
Paper 1
2 hours 30 minutes
Candidates answer on the Question Paper.
No Additional Materials are required.
READ THESE INSTRUCTIONS FIRST
Write your Centre number, candidate number and name on all the work you hand in.
Write in dark blue or black pen.
You may use a soft pencil for any diagrams, graphs or rough working.
Do not use staples, paper clips, highlighters, glue or correction fluid.
DO NOT WRITE IN ANY BARCODES.
Answer all questions.
No marks will be awarded for using brand names of software packages or hardware.
At the end of the examination, fasten all your work securely together.
The number of marks is given in brackets [ ] at the end of each question or part question.
For Examiner's Use
This document consists of 19 printed pages and 1 blank page.
IB10 06_7010_12/FP
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1
Explain, with examples where appropriate, the following five computer terms.
For
Examiner's
Use
(a) buffer
[2]
(b) batch processing
[2]
(c) e-commerce
[2]
(d) simulation
[2]
(e) email
[2]
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2
A company making televisions has introduced robots to replace the human work force.
For
Examiner's
Use
(a) Describe three effects this would have on the work force.
1
2
3
[3]
(b) Give two advantages to the company of introducing robots.
1
2
[2]
(c) How could the robots be trained to assemble the televisions?
[1]
(d) A whole batch of televisions was produced with some of the parts missing. How could
this error have been avoided?
[1]
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4
Give four features of a Data Protection Act.
1
2
3
4
[4]
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5
A bank is worried about computer crime.
For
Examiner's
Use
One of their concerns is online access to customer accounts.
(a) How can a customer’s access details be discovered by criminals?
[2]
(b) Why would a customer using a credit card for online shopping be more of a security
risk than a customer using the same card in a shop?
[2]
(c) Describe what measures the bank can take to safeguard customer accounts.
[2]
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6
An expert system is being developed to help engineers diagnose faults in aero engines.
For
Examiner's
Use
(a) Describe the steps taken to develop this new expert system.
[4]
(b) Another method used to identify and rectify faults is to train engineers using
virtual reality systems.
(i) What is virtual reality?
[1]
(ii) What special hardware is used to interface with virtual reality systems?
[1]
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7
A screen has been developed to allow the input of data into the following fields:
name, sex, address, date of birth and examination results.
For
Examiner's
Use
(a) A first attempt at designing the screen is shown below:
Student Records
Student name: ………………………………….. Sex: ……………………
Student address: ………………………………………………………………
…………………………………………………………………………………….
Date of birth: ……… / ……… / ………
Exam results: Subjects and Grades
Type in NEXT to go to next student or BACK to go to previous
student: …………………………
This is not a very good input screen. Give four ways in which it could be improved.
1
2
3
4
[4]
(b) (i) What is verification?
(ii) Which fields should be verified?
[3]
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8
A supermarket makes use of barcodes on all its goods as part of its automatic stock control
system.
(a) Describe how the price is found for each item sold.
[2]
(b) The following are steps in the automatic stock control system.
Number the steps in the correct order.
if stock level ≤ minimum stock level
report printed out for the manager
stock level reduced by 1
new stock value written back to file
more items are ordered automatically
[4]
9
A factory uses a computer system to store information about customers, spare parts and
general administration.
(a) Spare parts can be identified by selecting from diagrams on a computer screen.
Describe what hardware would be needed to allow the parts to be selected in this way.
[2]
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Use
.
67
(b) The factory needs to buy a new printer. It has decided to buy either a dot matrix printer
or an inkjet printer. Discuss the advantages and disadvantages of using both types of
printer in this application.
For
Examiner's
Use
Dot matrix printer:
Advantages
Disadvantages
[3]
Inkjet printer:
Advantages
Disadvantages
[3]
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0
10 A small company runs six cars in its fleet. They have produced a spreadsheet to compare
running costs over a five month period:
A
Car Identity
1
2
3
4
5
6
7
8
10001
10002
10003
10004
10005
10006
B
Total number
of km
30 000
20 000
50 000
30 000
20 000
30 000
Averages:
C
Cost per km
($)
1.00
4.00
1.50
2.00
2.50
1.50
2.08
D
Total cost
($)
30 000
80 000
75 000
60 000
50 000
45 000
56 667
E
Average cost
per month ($)
6 000
16 000
15 000
12 000
10 000
9 000
11 333
(a) It was decided to print out the spreadsheet formulas from D2 to E8. Using the grid
below, show what formulas would be printed:
1
D
Total cost
($)
E
Average cost
per month ($)
2
3
4
5
6
7
8
[4]
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Use
.
69
(b) A graph of Cost per km ($) was drawn:
For
Examiner's
Use
Cost per km ($)
4.5
Cost per km ($)
4
3.5
3
2.5
2
1.5
1
0.5
0
10001
10002
10003
10004
10005
10006
Car identity
(i) Which cells were highlighted to produce this graph?
[2]
(ii) Describe how the average value of 2.08 would be shown on the graph.
[1]
(c) The data in cell C6 was changed to 3.00.
Which cells would be updated automatically?
[2]
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2
11 A database has been set up showing information about cars:
Car ref
No of
doors
Engine
(litres)
CO2
(g/km)
Fuel used
(km/litre)
No of
cylinders
A
3
1.4
145
15.3
4
B
4
2.0
193
12.3
4
C
5
2.5
231
10.9
6
D
3
2.0
190
11.2
6
E
4
1.3
120
17.5
4
F
5
1.8
180
14.6
4
G
4
3.0
240
9.5
6
H
4
1.2
115
19.7
3
For
Examiner's
Use
(a) Using Car ref only, write down which cars would be output if the following search
condition was used:
(No of doors = 4) AND (Fuel used (km/litre) > 15)
[2]
(b) Write down a search condition to find out which cars have engines larger than 1.8 litres
OR have CO2 emissions higher than 150 g/km.
[2]
(c) The database is sorted in ascending order on Fuel used (km/litre). Using Car ref
only, write down the results of the sort.
[2]
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3
12 (a) State two items of hardware needed to enable a standard computer system to take
part in video conferencing.
For
Examiner's
Use
1
2
[2]
(b) State two additional items of software that would be needed for the video conferencing
to take place.
1
2
[2]
(c) Describe two potential problems when using video conferencing.
1
2
[2]
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4
13 Study the following flowchart very carefully:
For
Examiner's
Use
START
INPUT X
Yes
Is X = 0?
No
PRINT
“error”
STOP
T=X
N=1
T = T/10
N=N+1
No
Yes
Is T < 10?
PRINT N
STOP
What output would you expect if the following data was input into the flowchart?
X
OUTPUT
-150
540
0
[3]
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5
14 A safety system has been developed to stop vehicles getting too close to each other on the
road.
A
B
For
Examiner's
Use
sensors
If vehicle A gets too close to vehicle B, the brakes are automatically applied by a computer
system in vehicle A.
(a) What type of sensors could be used on the vehicles?
[1]
(b) Describe what the safety system does to constantly monitor how close the vehicle is to
the vehicles in front and decide when to take action.
[4]
(c) Describe two potential problems with this safety system.
1
2
[2]
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6
15 A floor turtle can use the following instructions:
Instruction
For
Examiner's
Use
Meaning
FORWARD d
Move d cm forward
BACKWARD d
Move d cm backward
LEFT t
Turn left t degrees
RIGHT t
Turn right t degrees
REPEAT n
Repeat the next set of instructions n times
ENDREPEAT
End of REPEAT loop
PENUP
Raise the pen
PENDOWN
Lower the pen
(In the following grid, each square is 10 cm by 10 cm.)
Start
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7
Complete the set of instructions to draw the shape (shown in bold lines) by filling in the
blank lines.
For
Examiner's
Use
LEFT 90
PENDOWN
FORWARD 10
RIGHT 90
[5]
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8
16 (a) Write an algorithm, using pseudocode or a flowchart, which:
For
Examiner's
Use
inputs 50 numbers
outputs how many of the numbers were > 100
[3]
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9
(b) Write an algorithm, using pseudocode or a flowchart, which:
For
Examiner's
Use
inputs 100 numbers
finds the average of the input numbers
outputs the average
[3]
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UNIVERSITY OF CAMBRIDGE INTERNATIONAL EXAMINATIONS
GCE Ordinary Level
MARK SCHEME for the May/June 2010 question paper
for the guidance of teachers
7010 COMPUTER STUDIES
7010/12
Paper 12, maximum raw mark 100
This mark scheme is published as an aid to teachers and candidates, to indicate the requirements of
the examination. It shows the basis on which Examiners were instructed to award marks. It does not
indicate the details of the discussions that took place at an Examiners’ meeting before marking began,
which would have considered the acceptability of alternative answers.
Mark schemes must be read in conjunction with the question papers and the report on the
examination.
•
CIE will not enter into discussions or correspondence in connection with these mark schemes.
CIE is publishing the mark schemes for the May/June 2010 question papers for most IGCSE, GCE
Advanced Level and Advanced Subsidiary Level syllabuses and some Ordinary Level syllabuses.
M.Mushtaq
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Mark Scheme: Teacher version
GCE O LEVEL – May/June 2010
Syllabus
7010
Paper
12
(a) buffer
Any two points from:
– temporary …
– … storage/memory
– compensates for the difference in speed of peripherals and CPU
– e.g. printer (buffer)
[2]
(b) batch processing
Any two points from:
– processing doesn’t start until all data is collected
– JCL (any reference to Job Control Language)
– no need for user interaction
– processed all in one go
– done at “quiet” times
– e.g. billing, payroll, cheque processing
[2]
(c) e–commerce
Any two points from:
– electronic commerce
– buying and selling products/services …..
– ….. using the internet/computer networks
– reference to B2B (business to business)
or B2C (business to consumer/customer)
– e.g. on-line shopping, commodity exchanges, Internet/online banking
[2]
(d) simulation
Any two points from:
– studying the behaviour of a system
– by using a model/mathematical representation
– results can be predicted
– e.g. flight (or other) simulator, modelling hazardous chemical processes
– e.g. 10-pin bowling computer game
[2]
(e) email
Any two points from:
– electronic mail
– sending messages from one device to another using computer networks/Internet
– world wide form of electronic communication
– can send file attachments
– e.g. sending a letter without use of traditional mail service
[2]
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Mark Scheme: Teacher version
GCE O LEVEL – May/June 2010
Syllabus
7010
Paper
12
(a) Any three points from:
– loss of jobs/unemployment
– deskilling
– need to re-train
– different jobs available/re-skilling
– no longer need to do hazardous/tedious jobs
[3]
(b) Any two points from:
– lower work force costs (no salaries to pay)
– lower environmental costs (less electricity for heating/lighting)
– higher throughput
– more consistent product
– robots don’t need breaks, holidays/work 24/7 etc.
– robots don’t take industrial action
[2]
(c) Any one point from:
– tasks repeated by skilled worker and how each task is done is memorised
– tasks programmed directly into the computer/robot memory
[1]
(d) Any one point from:
– if parts missing for a sequence, then a warning should be given and the assembly
stopped
– several quality control stages to spot an error early on
– program in checks at each stage of assembly so robots can detect a fault immediately [1]
3
4
Any four points from:
– understand the current system
– produce data flow diagrams/system flowchart
– identify user/client requirements/objectives
– interpret user/client requirements/objectives
– agree requirements/objectives with the user/client
– collect data from the current system
– fact finding (e.g. questionnaires, interviewing, etc.)
– problem identification
[4]
Any four features from:
– data must be up to date
– data can only be read/used for the purpose for which it was collected
– data must be adequate, relevant and not excessive
– data must be accurate
– data must be destroyed when no longer needed/don’t keep longer than necessary
– data user must register what data stored
– data must be used/collected fairly and lawfully
– data must be held securely
– data must be protected from accidental damage
– only authorised personnel can have access to the data
– fines are imposed for data mis-use
– data should not be passed on to a third party without permission
– a person can view data and have it changed/removed if incorrect
– safe harbour (countries with DPA at least as good)
[4]
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(a) 1 mark each for 2 concerns
OR 1 mark for concern + 1 mark for expansion:
–
–
–
6
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customer goes online in a public place …..
…… and is overlooked as they enter id/password/PIN
customer receives emails taking them to a false site …..
….. where they are asked to confirm details by entering them
customer downloads virus, spyware, …..
….. which logs all key presses including id/password/PIN
[2]
(b) Any two points from:
– don’t need card number for online transaction/card number already
– online user is anonymous/not visible
– online the customer does not need the card and signature/PIN
[2]
(c) Any two points from:
– secure sites using encryption
– use of passwords/PINs/biometrics/advice to change PIN regularly
– no communications with customer requiring personal details
– use of home card readers that generate codes known only to bank
and customer
– check with customer at each log on when they were last logged on to the
website
– contact customer if unusual transaction/random check
– customer asked to inform bank if intending to use card in
another country
– customer asked to inform bank if card lost/stolen
– ensure firewall is in place
[2]
(a) Any four points from e.g.:
– gather information from experts/questionnaires
– create the knowledge base
– type/put information into computer
– create rules/rules base
– create/design inference engine
– create/design input–output interface
– fully test the system
– expert system learns
[4]
(b)
(i) Any one point from:
– 3D visual world
– uses computer simulation
– uses special interface devices (e.g. data gloves and goggles)
[1]
(ii) Any one point from:
– data gloves/goggles (if not given credit in part (i))
– hardware/motors to provide movement
– special suits fitted with sensors
[1]
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Page 5
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Paper
12
(a) Any four improvements from:
– use (text) boxes for
– names
– addresses
– sex
– date of birth
– subjects
– grades
– separate fields into separate entry items
– name into first name and last name
– address into street, city etc
– drop down list/combo box for
– date of birth
– sex
– subjects
– grades
– calendar object for
– date of birth
– radio buttons for
– sex
– hyperlinks for
– NEXT
– BACK
(b)
(i)
–
–
–
[4]
any one point from:
check on input for errors by double entry
on screen checking
check input is same as source
(ii) –
–
8
Syllabus
7010
name
address
[3]
(a) Any two points from:
– barcode is scanned/keyed in
– barcode is validated (by check digit)
– system looks up barcode in computer files/database
– retrieves (and returns) price
[2]
(b)
if stock level < minimum stock level
report printed out for manager
stock level reduced by 1
new stock value written back to file
more items are ordered automatically
3
5
1
2
4
1 mark for each correct answer up to max of 4.
4 marks for all 5 correct
3 marks for any 3 or 4 correct
2 marks for any 2 correct
1 mark for any 1 correct
[4]
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Syllabus
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Paper
12
(a) Any two correct input devices
OR input device + correct type of screen
– mouse/trackerball + CRT screen/TFT screen
– touch screen + CRT screen/TFT screen
– light pen + CRT screen
[2]
(b) Dot matrix printer:
Accept a max of 2 advantages and a max of 2 disadvantages:
Advantages:
– suitable for dirty/dusty/damp atmospheres
– cheap to maintain
– cheap to run
– can operate with continuous/multipart stationery
Disadvantages:
– poor print quality
– very noisy
– very limited colours
[3]
Inkjet printer:
Accept a max of 2 advantages and a max of 2 disadvantages:
Advantages:
– inexpensive to purchase
– high quality printouts
– can use colours
– supported by most operating systems
– quiet
Disadvantages:
– run out of printing ink quickly/cartridges run out quickly
– price per page/inks are expensive
– not suitable for dirty/dusty/damp atmospheres
[3]
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Page 7
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Paper
12
10 (a) Award marks as shown (each block = 1 mark):
D
Total cost
($)
E
Average cost
per month ($)
2
= B2 * C2
= D2 / 5
3
= B3 * C3
= D3 / 5
4
= B4 * C4
= D4 / 5
5
= B5 * C5
= D5 / 5
6
= B6 * C6
= D6 / 5
7
= B7 * C7
= D7 / 5
8
= AVERAGE (D2 : D7)
= AVERAGE (E2 : E7)
1
Alternative answers:
Alternative answers:
= SUM(D2:D7)/6
= SUM(E2:E7)/6
= (D2+D3+D4+D5+D6+D7)/6
= (E2+E3+E4+E5+E6+E7)/6
= D8/5
[4]
(b)
(i) (A1 : A7) and (C1 : C7)
(1 mark)
(1 mark)
[2]
(ii) Any one point from:
– add an extra column and set all values to 2.08
– draw a line at value 2.08 on the graph
– add a trend/average line using spreadsheet software
[1]
(c) D6, E6, C8, D8, E8 (-1 mark for each error or omission)
11 (a)
(b)
(c)
[2]
E, H
[2]
(Engine (litres) > 1.8) OR (CO2 (g/km) > 150)
← (1 mark)
→ ←
(1 mark)
→
Or
(CO2 (g/km) > 150) OR (Engine (litres) > 1.8)
← (1 mark)
→ ←
(1 mark)
→
[2]
G, C, D, B, F, A, E, H
(1 mark for correct order (fuel used)
1 mark for ascending order)
[2]
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Paper
12
12 (a) Any two items from:
– webcams/digital video camera
– microphones
– broadband modem
– networking hardware e.g. cabling/router
– loud speakers/headphones
[2]
(b) Any two items from:
– communications software
– CODEC/compression software
– Internet access software
– driver software (for the hardware in part (a))
– echo cancellation software
[2]
(c) Any two problems from:
– poor reception (poor sound, jerky screen images)/network failure
– if more than 2 conference locations, can be difficult controlling meeting
– time zones
– language difficulties
– power failure
[2]
13 Expected output:
1
2
Error
[3]
14 (a) Any one from:
– infra-red
– light
– radar
– ultrasonic / proximity
[1]
(b) Any four points from:
– signal sent out from vehicle A
– sensors pick up reflected beam
– signal converted to digital by ADC
– computer uses data to calculate how close vehicle B is
– computer uses speed of vehicle A …..
– ….. to determine the safe distance
– if the safe distance > distance between the two vehicles …..
– ….. then the driver is warned
– sends signal to (actuators) apply brakes
– reference to need for DAC
– monitoring continues endlessly unless system deactivated
* no marks for computer applies the brakes
* no marks for computer senses ….
* no marks for sensor taking any actions
[4]
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12
(c) Any two points from:
– when roads are busy, constantly braking
– system may not take road conditions into consideration
– over-reliance on system by the driver
– only works properly if vehicle has an automatic gearbox
– sensors don’t work if obstructed/dirty/malfunction
15 LEFT 90
PENDOWN
FORWARD 10
RIGHT 90
––––––––––––––––––––
FORWARD 10
PENUP
FORWARD 10
PENDOWN
––––––––––––––––––––
FORWARD 20
RIGHT 90
FORWARD 20
RIGHT 90
FORWARD 20
––––––––––––––––––––
LEFT 90
FORWARD 20
PENUP / RIGHT 90
––––––––––––––––––––
[2]
20 RIGHT 90/PENUP
FORWARD 10
PENDOWN
––––––––––––––––––––
FORWARD 10
RIGHT 90
FORWARD
(NOTE: the second sequence of instructions could be done with a REPEAT loop i.e. REPEAT 2
FORWARD 20
RIGHT 90
ENDREPEAT
FORWARD 20
It is also possible to write:
REPEAT 3
FORWARD 20
RIGHT 90
ENDREPEAT
followed by LEFT 180 or RIGHT 180 instead of LEFT 90)
16 (a) total = 0
for x = 1 to 50
input number
[5]
(1 mark)
(1 mark)
initialisation
correct loop
(1 mark)
correct input and output
if number > 100 then total = total + 1
(1 mark)
count numbers>100
next x
output total
(1 mark for initialising total)
(1 mark for correct loop – accept repeat loop or a while loop)
(1 mark for correct input (within loop) and output (after the loop))
(1 mark for counting how many input numbers were > 100)
[3]
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Page 10
(b) total = 0
for x = 1 to 100
(1 mark)
initialise total
(1 mark)
correct loop
input number
(1 mark) correct input and output
total = total + number
(1 mark) finding sum of numbers
Syllabus
7010
Paper
12
next x
average = total/100
(1 mark) calculate average
output average
(1 mark for initialising total)
(1 mark for correct loop – accept repeat loop or a while loop)
(1 mark for correct input (inside the loop) and output (after the loop))
(1 mark for calculating total)
(1 mark for calculating the average outside the loop)
[3]
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UNIVERSITY OF CAMBRIDGE INTERNATIONAL EXAMINATIONS
General Certificate of Education Ordinary Level
*2050555414*
7010/11
COMPUTER STUDIES
October/November 2010
Paper 1
2 hours 30 minutes
Candidates answer on the Question Paper.
No Additional Materials are required.
READ THESE INSTRUCTIONS FIRST
Write your Centre number, candidate number and name on all the work you hand in.
Write in dark blue or black pen.
You may use a soft pencil for any diagrams, graphs or rough working.
Do not use staples, paper clips, highlighters, glue or correction fluid.
DO NOT WRITE IN ANY BARCODES.
Answer all questions.
No marks will be awarded for using brand names of software packages or hardware.
At the end of the examination, fasten all your work securely together.
The number of marks is given in brackets [ ] at the end of each question or part question.
For Examiner's Use
This document consists of 20 printed pages.
IB10 11_7010_11/FP
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1
Explain, using examples where appropriate, the following five computer terms:
For
Examiner's
Use
(a)
Check digit
[2]
(b)
RAM
[2]
(c)
Macro
[2]
(d)
USB flash memory
[2]
(e)
Printer buffer
[2]
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2
(a) State three reasons why a computer system failure might occur (malfunction).
For
Examiner's
Use
1
2
3
[3]
(b) One effect of a computer system failure is the loss or corruption of files. State one way
of recovering a file if it has been lost or corrupted.
[1]
(c) How is it possible to ensure illegally accessed files are unreadable?
[1]
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3
(a) Name the following network topologies:
Name: …………………………
For
Examiner's
Use
Name: …………………………..
[2]
(b) Give one advantage of having computers connected on a network.
[1]
(c) Give one disadvantage of having computers connected on a network.
[1]
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4
(a) To log on to a computer, a user needs to type in a user id followed by a password;
these should match up. Only three attempts are allowed.
For
Examiner's
Use
The flowchart below shows the log on procedure. Several boxes have been left blank.
Complete the flowchart using items from the list.
START
List
Enter user
id
1
2
3
4
5
6
7
Access not allowed
Allow access
Do user id and password match?
Enter password
Error message
Error message
Three attempts?
Yes
No
Yes
No
STOP
[3]
(b) Sometimes it is necessary to key in the password twice.
Name this type of data check.
[1]
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5
A large cinema uses a computer system to control the air conditioning and also the day to
day running of the business (such as booking seats).
(a) Using examples from the cinema application, explain the difference between real time
transaction processing and real time process control.
[4]
(b) State two tasks carried out by an operating system.
1
2
[2]
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.
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6
A telephone company produces paper-based directories. It has decided to offer directory
information to customers via a website.
For
Examiner's
Use
(a) Give one advantage to the telephone company in doing this.
[1]
(b) What two advantages does this new system offer the customer?
1
2
[2]
(c) Give one disadvantage to the customer of having their details available on the Internet.
[1]
(d) Describe one problem with the existing paper-based system that would not be
resolved using the electronic version.
[1]
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(d) Give two advantages of using a computer system rather than a manual system.
For
Examiner's
Use
1
2
[2]
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0
8
A company has set up video conferencing facilities connecting Rio de Janeiro, New York
and Hong Kong.
New York
Hong Kong
Rio de Janeiro
(a) Give one hardware item and one software item needed at each video conferencing
location.
Hardware item
Software item
[2]
(b) Describe two possible problems with this video conferencing set up.
1
2
[2]
(c) Apart from travelling and accommodation costs, what two benefits does the company
gain from using video conferencing facilities?
1
2
[2]
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Use
.
97
9
The following algorithm inputs 20 numbers and outputs how many numbers were positive
(> 0) and how many numbers were negative (< 0).
1
2
3
4
5
6
7
8
9
For
Examiner's
Use
negative = 1
positive = 1
for count = 1 to 20 do
input number
if number < 0 then negative = negative + 1
if number > 0 then positive = positive + 1
count = count + 1
print negative, positive
next count
There are three different errors in this algorithm.
Locate each error and give the reason why you think it is an error.
Error 1
Reason 1
Error 2
Reason 2
Error 3
Reason 3
[6]
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2
10 A database has been set up to store information about aircraft. A section is shown below.
Ref
No
1001
2001
3001
3002
2002
3003
3004
2003
3005
3006
3007
Aircraft Name
An-225 Cossack
Airbus A380F
C-5 Galaxy
Boeing 777-600
Airbus A340-600
Boeing 747
Boeing 777
Airbus A330-300
Boeing 767
B52 Fortress
Boeing 757
Max Weight
(kg)
600 000
591 950
381 000
351 500
366 000
397 000
660 000
234 000
204 100
221 400
123 400
Length
(m)
84
73
76
74
75
71
74
63
61
49
54
Wing
Span (m)
88
80
68
65
63
64
61
60
52
56
38
Max Speed
(kph)
850
951
845
930
877
967
893
800
914
927
914
(a) How many fields are in each record?
[1]
(b) Using Ref No only, what records would be output if the following search condition was
entered:
(Max Weight(kg) > 350 000) AND (Wing Span(m) < 66)?
[2]
(c) Write down the search condition to find out which aircraft have a length greater than
74 metres or have a maximum speed less than 900 kph.
[2]
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3
11 A road system is to be operated using computer-controlled traffic lights. Sensors are used
as part of the control system.
For
Examiner's
Use
(a) The movement of traffic throughout the road system was first simulated on a computer.
Describe what data would need to be collected and how it would be used in the
simulation.
[3]
(b) Give two advantages of carrying out a simulation first before introducing a new system.
1
2
[2]
(c) Describe how the sensors, traffic lights and computer interact to control the traffic flow
in the new system.
[2]
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4
12 A holiday resort is developing a website to inform the general public about their weather.
A spreadsheet was produced to show some of the statistics:
A
1
2
3
4
5
6
Monthly
Rainfall
(mm)
Hours
Sunshine
(per day)
Minimum
Temperature
(C)
Maximum
Temperature
(C)
Sun Index
For
Examiner's
Use
B
C
D
E
F
G
H
I
J
K
L
M
N
Jan
Feb
Mar
Apr
May
Jun
Jul
Aug
Sep
Oct
Nov
Dec
Averages
130
210
340
350
220
170
100
30
25
20
10
50
138
7
6
6
6
7
8
8
6
9
9
10
8
8
29
28
27
25
23
22
20
22
24
26
27
28
25
36
34
32
30
28
27
25
28
31
33
36
38
32
49
36
28
28
35
40
40
36
63
63
90
80
(a) What formula is in N2 to show the average (mean) rainfall?
[1]
(b) Row 6 shows the Sun Index which is the difference between maximum temperature and
minimum temperature multiplied by hours sunshine. What formula is in L6 to calculate
the sun index for November?
[1]
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5
(c) The resort wanted to show Hours Sunshine and Monthly Rainfall on one graph. Graphs
A and B were produced:
GRAPH A
(i)
Which is the best graph for
showing this information? Give a
reason for your answer.
(ii)
The resort wanted to include
average Hours Sunshine on the
graph. Describe how this could be
done.
12
10
8
6
4
2
0
400
300
200
100
Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
rainfall (mm)
hours sun
Sunshine (hours) and Rainfall (mm)
For
Examiner's
Use
0
month
SUN
RAIN
GRAPH B
rainfall (mm)
400
300
200
100
0
Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
12
10
8
6
4
2
0
hours sun
Sunshine (hours) and Rainfall (mm)
month
RAIN
SUN
[2]
(d) Apart from the information shown already, what two features would you expect to see
on the resort’s website?
1
2
[2]
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6
13 Describe how an expert system is developed and made ready for use.
For
Examiner's
Use
[4]
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7
14 An international bank keeps records of customer account details on a computer.
For
Examiner's
Use
(a) It is necessary on occasions to:
•
•
•
delete records
amend records
insert records
Give one example of when each of the above would need to be done.
Delete
Amend
Insert
[3]
(b) A section of one record is shown below:
Frederick Parez
Rua Silva Paulet
name
address
5151 315 000
34
20 − 15 − 00
telephone number age
branch
Br
country
(i) The branch and country are coded. Give a reason for this.
[1]
(ii) One of the six fields is not appropriate.
Name this field and give a reason for your choice. Suggest an improved field.
Name of field
Reason for choice
Improved field choice
[3]
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8
15 A college secretary inputs data into fields on a computer screen as shown below:
For
Examiner's
Use
Examination Results
Student Sex:
Today’s Date:
Examination Result (%):
Subject:
Grade:
(a) Choose a suitable different validation check for each of the following:
(i) Student Sex which can be M or F only
(ii) Today’s Date which must be written as, for example, 15/10/2010
(iii) the Examination Result which can be any number from 0 to 100
[3]
(b) Apart from validation, how would it be possible to ensure only certain data could be
input into each of the fields on the computer screen?
[1]
(c) The secretary takes a ten minute break every hour.
(i) Apart from switching off, how can the secretary make sure the computer system is
secure whilst she takes a ten minute break?
(ii) From a health and safety aspect, why does the secretary need to take regular
breaks?
[2]
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9
16
For
Examiner's
Use
Satellite navigation systems are used to give the vehicle driver directions.
(a) How does the system know the exact position of the vehicle?
[3]
(b) Give two advantages to the driver of using this system.
1
2
[2]
(c) Give one problem associated with satellite navigation systems.
[1]
(d) Name one other different form of transport which could use satellite navigation systems.
[1]
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0
17 A school is doing a check on the heights and weights of all its students. The school has
1000 students.
For
Examiner's
Use
Write an algorithm, using pseudocode or a flowchart, which
•
•
•
inputs the height and weight of all 1000 students
outputs the average (mean) height and weight
includes any necessary error traps for the input of height and weight
[5]
Permission to reproduce items where third party owned material protected by copyright is included has been sought and cleared where possible. Every
reasonable effort has been made by the publisher (UCLES) to trace copyright holders, but if any items requiring clearance have unwittingly been included, the
publisher will be pleased to make amends at the earliest possible opportunity.
University of Cambridge International Examinations is part of the Cambridge Assessment Group. Cambridge Assessment is the brand name of University of
Cambridge Local Examinations Syndicate (UCLES), which is itself a department of the University of Cambridge.
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UNIVERSITY OF CAMBRIDGE INTERNATIONAL EXAMINATIONS
GCE Ordinary Level
MARK SCHEME for the October/November 2010 question paper
for the guidance of teachers
7010 COMPUTER STUDIES
7010/11
Paper 1, maximum raw mark 100
This mark scheme is published as an aid to teachers and candidates, to indicate the requirements of
the examination. It shows the basis on which Examiners were instructed to award marks. It does not
indicate the details of the discussions that took place at an Examiners’ meeting before marking began,
which would have considered the acceptability of alternative answers.
Mark schemes must be read in conjunction with the question papers and the report on the
examination.
•
CIE will not enter into discussions or correspondence in connection with these mark schemes.
CIE is publishing the mark schemes for the October/November 2010 question papers for most IGCSE,
GCE Advanced Level and Advanced Subsidiary Level syllabuses and some Ordinary Level
syllabuses.
M.Mushtaq
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(a) check digit
– validation check
– single digit appended to a number
– calculated from digits and their position
– re-calculated after data transfer
–
e.g. bar codes, ISBN, credit/debit cards
[2]
(b) RAM
– random access memory
– memory lost on switching off/volatile/temporary
– stores user programs/data (etc.)
– usually on a chip
– can be read/changed by user
e.g. SRAM,DRAM etc.
[2]
(c) macro
– macro instruction
– new command created by combining number of existing ones
– can combine effects of pressing several individual keys on k/board
– can be programmed by user to customise software
– e.g. single key stroke to insert a logo into a document
[2]
(d) USB flash memory
– (memory data) storage device
– removable/portable
– uses universal serial bus connector
– re-writable device
– contains printed circuit board
– allows transfer of data/files between computers
– draws power from the computer port
– contains EEPROM (electrically erasable programmable ROM)/ non-volatile memory
– e.g. pen drive/memory stick/thumb drive
[2]
(e) printer buffer
– temporary storage/memory
– compensates for the difference in speed of printer and CPU
– e.g. holds data whilst computer completes a job, recovering from error (e.g. paper jam)
[2]
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(a) Any three from:
– “glitches in the software” e.g. divide by zero
– software conflicts
– virus
– operating system software loss/corruption
– hardware malfunction (e.g. overheating of circuit board, processor fans failing etc.)
– hardware incompatibility
– power supply interruption/”spikes”
– incorrect power down after use
– hard disk crash/failure
[3]
(b) Any one from:
– Grandfather-Father-Son (GFS)/file generation system
– backups
– parallel systems
– type/scan and OCR in new data again from the hard copies
[1]
(c) Any one from:
– encryption
– encrypt files
[1]
3
(a) STAR, BUS
[2]
(b) Any one from:
– can use any station to access files, etc.
– can share files etc.
– can share resources (e.g. printer)
– allows easier communication between users
[1]
(c) Any one from:
– more easily/more rapid transfer of viruses from computer to computer
– file (etc.) security is more difficult
– extra infrastructure costs e.g. cabling
[1]
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(a)
START
Enter user
id
4
1 mark
6 (or 5)
Yes
3
2
No
Yes
7
5 (or 6)
1 mark
1 mark
No
1
STOP
1
2
3
4
5
6
7
Access not allowed
Allow access
Do user id and password match
Enter password
Error message
Error message
Three attempts
[3]
(b) verification
[1]
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(a) 2 marks (max) for RTTP points; 2 marks (max) for RTPC points
real time transactions
real time processing
–
individual transaction processed as
it occurs
–
–
files/fields/records updated
immediately
–
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e.g. online booking of seats
–
–
physical quantities continuously
monitored
inputs compared with pre-set values
processed fast enough to affect input
–
uses sensors, ADC, DAC, etc.
–
e.g. temperature control in air con
[4]
(b) Any two points from:
– file management
– input/output control
– spooling
– memory management
– multiprogramming
– multitasking/JCL/batch processing
– handling interrupts
– error reporting/handling
– security (e.g. virus checking)
– user interface (e.g. WIMP)
– processor management
– loads/runs programs
– user accounts
– utilities
[2]
(a) Any one from:
– reduced costs (no/less printing, no/less distribution of directories)
– faster/easier updating procedure
– raising profile of company
[1]
(b) Any two from:
– faster/easier to find information
– more accurate/up-to-date
– more information/data available
– could easily extend to international directories
[2]
(c) Any one from:
– more likely to get calls from call centres/sales companies
– unsolicited calls
– mis-use of details
[1]
(d) Any one from:
– number changed and not registered
– errors in the information
[1]
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11
(a) (i) Any one from:
–
–
interview customers
hand out questionnaires to customers
[1]
(ii) 1 mark for method and 1 mark for reason:
8
–
–
DIRECT
must have only one way of conveying/updating the information
–
–
PILOT
could adopt new system at one terminal only to trial new system
–
–
PARALLEL
Check new system is working correctly/back up in case of system failure
[2]
(b) Any one from:
– current time
– terminal number/name
– date
– baggage reclaim/carousel number
– name of airline
– transfers/connections
[1]
(c) Any one from:
– touch screens/touch pad/mouse/tracker ball
[1]
(d) Any two from:
– fewer errors
– could be linked to website for live updates
– faster/more accurate updating of information
– no language problems for customers
– no need to wait in a queue at manned help desks
[2]
(a) 1 mark for hardware and 1 mark for software:
hardware
– webcam
– microphone
– large TV/monitor/screen
– router/broadband modem
– communications cables
– speakers
software
– compression software/CODEC
– communications software
[2]
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(b) Any two from:
– language differences
– time differences
– controlling a 3-way conversation
– possible poor communications/loss of connection/slow connection
– delay in transmission
[2]
(c) Any two from:
– less time lost in travelling
– can hold meetings with little notice
– safer (must be qualified e.g. terrorism risk, less travelling, etc.)
– can involve more people company-wide
[2]
1 mark for each error and 1 mark for reason why it is an error
–
line 1/negative=1 and/or line 2/positive=1
–
negative and/or positive should be set to zero
–
–
–
line 7/count=count+1
don’t need a count within a for …. to next loop
replace loop with a repeat...until loop
–
–
line 8/print negative, positive or line 9/next count
outputs should come after the next count statement
[6]
10 (a) 6 (fields)
[1]
(b) 3002, 2002, 3003, 3004
(c) (Length (m) > 74)
← - (1 mark) - →
OR
[2]
(Max Speed (kph) < 900)
← - - - - - - (1 mark) - - - - - - →
OR
(Max Speed (kph) < 900)
← - - - - (1 mark) - - - - →
OR
(Length (m) > 74)
← - - - (1 mark) - - - →
[2]
11 (a) Any three points from:
– (count) number of vehicles …
– … at various times of day/at different positions/in different directions
– put data into computer …
– … and try out different scenarios
– look at effect of accidents/break downs
– look at effect of heavy traffic
– determine optimum timings of lights
– effect of emergency vehicles/public transport
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(b) Any two from:
–
–
–
–
less expensive (must be qualified)
much safer prevents accidents/traffic problems through incorrect lighting times
can try out many scenarios first (to give optimum settings)
much faster than doing actual “experiments” on real lights
[2]
(c) Any two from:
–
–
–
–
–
–
–
–
sensors detect cars at each junction
sends signals/data to computer
computer software counts number of cars
if analogue data, need an ADC
compares sensor data with stored data/simulation results
changes light timings/sequences as required
(uses DAC) to send signals back to lights (control)
continuously monitors
[2]
12 (a) = SUM(B2:M2)/12
OR
= AVERAGE(B2:M2)
OR
= (B2+C2+D2+E2+F2+G2+H2+I2+J2+K2+L2+M2)/12
[rounded]
[1]
(b) = (L5 – L4) * L3 (must use cell references)
[1]
(c) (i) graph “B” since rainfall usually measured as a height/bars
graph “B” since the information is clearer
[1]
(ii) –
–
draw a line at value 8
include a row with all values 8 and add this data
[1]
(d) Any two from e.g.
– weather forecast for 7/14 days
– attractions/facilities in the area
– online booking e.g. hotels
– maps/how to get there
– buttons linking to other web pages/site
– videos/multimedia presentations
– search facility
– images of resort/virtual tours
[2]
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13 Any four from:
– collect information from expert(s)
– put information into the/create knowledge base
– develop YES/NO dialogue/user interface
– output screens designed
– fully tested with known expected outputs
– produce user manuals
– fully train users of the system
– reference to inference engine being created
– reference to rules base being created
[4]
14 (a) delete
–
–
customer leaves the bank/close account
customer dies
amend
–
–
–
–
–
change of address
change of telephone number
change account details
change name after marriage
transactions on account e.g. deposits, withdrawals
insert
–
new customer joins bank/opens new account
[3]
(b) (i) Any one from:
– saves memory/less space required on the file
– faster/easier to type in
– faster to search for information
– fewer errors
[1]
(ii) 1 mark for name, 1 mark for reason and 1 mark for improvement
–
–
–
–
AGE
always changing
need to keep updating each year
date of birth
[3]
15 EACH RESPONSE MUST BE DIFFERENT
(a) (i) Any one from:
– character/type check
– length check
– Boolean check
– presence check
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(ii) Any one from:
– format check
– character/type check
– length check
– presence check
(iii) Any one from:
– range check
– character/type check
– presence check
[3]
(b) Any one from:
– drop down lists showing M or F only, possible dates, etc.
– use of touch screens with only certain data options
– use of restricted lists
– radio buttons
[1]
(c) (i) Any one from:
– lock computer
– log off the system
– if in an office, lock the door
– put into sleep/hibernate mode with password
[1]
(ii) Any one from:
– to prevent RSI
– to prevent neck/back problems possible
– to prevent eye sight problems/headaches
[1]
16 (a) Any three from:
– satellites transmit signals to computer/sat nav in car
– sat nav system in car receives these signals
– depends on very accurate time references/atomic clocks
– each satellite transmits data indicating location and time
– sat nav system car calculates position based on at least 3 satellites
– at least 24 satellites in operation world wide
– sat nav system combines satellite information with mapping info
[3]
(b) Any two from:
– no need to read/own maps
– driver doesn’t need to memorise route
– can give useful information such as location of garages/speed cameras/points of
interest/traffic congestion
– allows driver to concentrate on driving (therefore safer)
– can find shortest/fastest route
– easier to re-route in case of road closures, etc.
– updateable
[2]
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(c) Any one from:
– stored maps out of date (instructions go to incorrect roads)
– inaccurate positioning
– loss of signal
– errors in original data/setting up
– sends vehicles down inappropriate routes
– over reliance by driver on the sat nav
[1]
(d) Any one from:
– ships
– aeroplanes
[1]
17 Marking Points
–
–
–
–
–
–
–
initialisation of running totals
correct loop control
error trap for height input
error trap for weight input
sum total1 and average1 (i.e. height) calculation
sum total2 and average2 (i.e. weight) calculation
correct output (only if some processing attempted, must be outside loop)
(1 mark)
(1 mark)
(1 mark)
(1 mark)
(1 mark)
(1 mark)
(1 mark)
[max: 5]
Sample pseudocode
total1 = 0: total2 = 0
(1 mark)
for x = 1 to 1000
(1 mark)
input height, weight
if height > 2 or height < 0 then print “error”: input height
(1 mark)
if weight > 130 or weight < 0 then print “error”: input weight
(1 mark)
else total1 = total1 + height: total2 = total2 + weight
next x
average1 = total1/1000
(1 mark)
average2 = total2/1000
(1 mark)
print average1, average2
(1 mark)
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UNIVERSITY OF CAMBRIDGE INTERNATIONAL EXAMINATIONS
General Certificate of Education Ordinary Level
*3512267971*
7010/13
COMPUTER STUDIES
October/November 2010
Paper 1
2 hours 30 minutes
Candidates answer on the Question Paper.
No Additional Materials are required.
READ THESE INSTRUCTIONS FIRST
Write your Centre number, candidate number and name on all the work you hand in.
Write in dark blue or black pen.
You may use a soft pencil for any diagrams, graphs or rough working.
Do not use staples, paper clips, highlighters, glue or correction fluid.
DO NOT WRITE IN ANY BARCODES.
Answer all questions.
No marks will be awarded for using brand names of software packages or hardware.
At the end of the examination, fasten all your work securely together.
The number of marks is given in brackets [ ] at the end of each question or part question.
For Examiner's Use
This document consists of 19 printed pages and 1 blank page.
IB10 11_7010_13/FP
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1
Explain, with examples where appropriate, the following five computer terms.
For
Examiner's
Use
(a) interrupt
[2]
(b) optical media
[2]
(c) CAD
[2]
(d) verification
[2]
(e) global positioning system (GPS)
[2]
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2
(a) What is meant by the term drop-down menu?
For
Examiner's
Use
[1]
(b) Give an example of where a drop-down menu could be used.
[1]
(c) Give one disadvantage of a drop-down menu.
[1]
3
A typical computer system contains the following four components:
RAM
ROM
hard disk
modem
Describe the function of each of these components.
RAM
ROM
hard disk
modem
[4]
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4
(a) Describe two differences between batch processing and real-time transaction
processing.
1
2
[2]
(b) Give one example of the use of each type of processing.
batch:
real-time transaction:
[2]
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5
Most laptop computers have networking capability.
(a) Describe two other desirable features you would look for when choosing a laptop
computer.
For
Examiner's
Use
1
2
[2]
(b) Describe two advantages of using broadband to connect to the Internet rather than
using dial-up.
[4]
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6
Complete the following table by writing down the most appropriate data collection method
for the given application.
Application
Data collection method
Reading information from a credit/debit
card
Choosing an option from a customer
information screen at an airport
Reading the results from a questionnaire
where pencil lines were used to choose
options
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8
Describe how computers are used to generate graphics and animation effects for use in
films and arcade games.
For
Examiner's
Use
[3]
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9
Students at a school decide to produce a monthly newsletter to inform parents of events.
They could either produce a magazine on paper or arrange for a multimedia presentation in
the school hall.
(a) State two advantages and two disadvantages of producing the magazine on paper.
Advantage 1
Advantage 2
Disadvantage 1
Disadvantage 2
[4]
(b) State two advantages and two disadvantages of giving a multimedia presentation.
Advantage 1
Advantage 2
Disadvantage 1
Disadvantage 2
[4]
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10 (a) What is meant by a virus?
For
Examiner's
Use
[2]
(b) What is meant by encryption?
[2]
(c) (i) A student wrote “I would make backup copies of my data to guard against viruses”.
Why is the student’s statement not necessarily true?
[1]
(ii) The same student also wrote “Encryption would stop a hacker accessing the data
in my computer files”.
Why is the student’s statement incorrect?
[1]
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0
11 (a) Which validation methods are being carried out by the following three pseudocode
statements?
(i) if age > 10 and age < 20 then print "correct"
(ii) if gender = "male" and title = "Mr" then print "correct"
(iii) if field = "" then print "input data is missing"
[3]
(b) Name a different validation technique and give an example to show how it works.
Name
Example
[2]
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12 (a) A student is trying to find out information about cloud computers.
For
Examiner's
Use
How could he use the Internet to find this information?
[2]
(b) Give two advantages of using the Internet to find information.
1
2
[2]
(c) Give two disadvantages of using the Internet to find information.
1
2
[2]
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2
13 A spreadsheet has been set up to compare the monthly costs of five mobile phone
networks. Normally a text message costs 2 cents and one minute of talk time costs
15 cents for all networks (100 cents = $1).
A
Network
name
Lemon
Yodafone
C-mobile
O-3
T-world
1
2
3
4
5
6
7
B
Monthly
charge ($)
65
65
65
65
65
C
No. of free
texts
500
1000
800
1000
2000
D
No. of free talk
time minutes
500
280
400
500
100
Best network:
E
Value of texts
+ talk time ($)
85
62
76
95
55
(a) What formula must be in E2 to calculate the value of the Lemon network offer?
[2]
(b) What formula needs to be placed in E7 to find the best offer?
[1]
(c) The customer actually uses 800 minutes of talk time per month.
How could the spreadsheet be modified so that the customer can find out which
network still gives him the best deal?
[2]
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3
14 An airport has a number of hotels nearby. A database has been set up to give customers
information to allow them to select a hotel.
Hotel
Ref
H41
K22
N15
L44
H30
H21
N21
K14
Name of
hotel
The Grand
Sleepy Inn
Britannia
Beach Hotel
Sea View
Pyramid
Superior
Travellers
No. of
stars
3
2
5
4
3
3
5
2
No. of
rooms
45
15
140
62
38
25
120
15
Hotel
parking
Y
N
Y
N
N
N
Y
N
Price per
person ($)
65
45
150
85
60
70
200
45
For
Examiner's
Use
Distance from
airport (km)
11
10
4
8
4
5
2
10
(a) How many records are shown in the database?
[1]
(b) Which field in each record must be unique?
[1]
(c) The following search condition was typed in:
(No. of stars > 3) OR (Hotel parking = Y)
Using Hotel Ref only, which records would be found?
[2]
(d) Write down the search condition to find which hotels were less than 10 km from the
airport and charged under $100 per person.
[2]
(e) The database was sorted into descending order using No. of rooms.
Using Hotel Ref only, write down the sorted order of records.
[2]
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4
15 (a) The following flowchart shows how a burglar alarm system uses light sensors to
determine if an intruder has entered the house and decides to sound an alarm.
Select statements from the list below, using numbers only, to complete the flowchart.
START
Light sensor
detects movement
List of statements
1
No
2
3
4
5
6
7
Yes
No
check sensor value with the
stored value
convert signal to digital
has alarm been re-set?
is a signal detected?
is sensor value nominal?
is signal digital?
sound an alarm
Yes
Yes
No
Yes
No
[4]
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5
(b) Explain why the sensor signal needs to be converted into digital.
For
Examiner's
Use
[2]
(c) Name a different sensor and describe an application that uses the named sensor.
Sensor name:
Description:
[2]
(d) The computer can’t directly control items such as motors and heaters.
What additional hardware is needed to allow the computer to control these devices?
[1]
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6
16 A customer logs on to a secure website using a code and a password. The first stage is to
key in a code which is his date of birth (DDMMYY) followed by 1234. The second stage is
to type in the first, third, fourth and seventh character of his password.
The customer last logged on to the website on 15th March 2010.
(a) (i) The customer’s date of birth is 15th November 1985. What is the customer’s
code?
(ii) Why is this code not unique?
(iii) Suggest how this coding system could be improved.
[3]
(b) (i) The customer’s password is PAULO168.
What does the customer need to type at the second stage?
1st
3rd
4th
7th
(ii) Why are passwords used?
[2]
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7
(c) If the customer gets through the two stages above he is then directed to a new security
page which states:
For
Examiner's
Use
“You were last logged on to this website on 14th April 2010. Is this correct?”
What could have happened to make the customer concerned about this statement?
[1]
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8
17 (a) Write an algorithm, using pseudocode or a flowchart, which
For
Examiner's
Use
inputs a set of positive numbers (which end with -1)
outputs the average (mean) value of the input numbers
outputs the value of the largest (highest) number input
[4]
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9
(b) Write an algorithm, using pseudocode or a flowchart, which
For
Examiner's
Use
inputs a whole number (which is > 0)
calculates the number of digits in the number
outputs the number of digits and the original number
(E.g. 147 would give an output of 3, 147)
[4]
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UNIVERSITY OF CAMBRIDGE INTERNATIONAL EXAMINATIONS
GCE Ordinary Level
MARK SCHEME for the October/November 2010 question paper
for the guidance of teachers
7010 COMPUTER STUDIES
7010/13
Paper 1, maximum raw mark 100
This mark scheme is published as an aid to teachers and candidates, to indicate the requirements of
the examination. It shows the basis on which Examiners were instructed to award marks. It does not
indicate the details of the discussions that took place at an Examiners’ meeting before marking began,
which would have considered the acceptability of alternative answers.
Mark schemes must be read in conjunction with the question papers and the report on the
examination.
•
CIE will not enter into discussions or correspondence in connection with these mark schemes.
CIE is publishing the mark schemes for the October/November 2010 question papers for most IGCSE,
GCE Advanced Level and Advanced Subsidiary Level syllabuses and some Ordinary Level
syllabuses.
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Mark Scheme: Teache s’ version
GCE O LEVEL – October/November 2010
Syllabus
7010
Paper
13
(a) Interrupt
Any two points from:
– a signal/request generated by a device/program
– which causes a break in the execution of the program/stops the program
– examples: printer out of paper, <BREAK> key pressed, disk full
[2]
(b) Optical media
Any two points from:
– type of non-magnetic memory
– uses light sensitive surface to store data
– media are very portable
– can be write once or write many times
– used to store large files
– can be ROM or RAM
– examples: CD, DVD
[2]
(c) CAD
Any two points from:
– computer aided design
– uses special hardware such as hi-res screen, plotters, spaceball
– makes use of features such as 2D, 3D, wire frames, costings, zoom
– use a library of spare parts
– often used with CAM
– examples: architecture designing buildings, car design, lighting at concerts
[2]
(d) verification
Any two points from:
– check on input for errors
– check before and after transfer (of signals)
– by double entry
– on screen checking
– comparing input/use of second operator
– e.g. typing in a password twice
[2]
(e) GPS
Any two points from:
– Global positioning system
– navigational system
– uses satellites
– which transmit data …
– … to determine exact location and time
– satellites use atomic/very accurate clocks
– sat nav computer calculates position based on satellite data
– examples: used in vehicles to find routes from a to B
[2]
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Mark Scheme: Teache s’ version
GCE O LEVEL – October/November 2010
Paper
13
(a) Any one point from:
– choose options by clicking on an arrow
– which highlights possible options
– uses a pointing device (e.g. mouse) to select
– list of items to select/click on
– an inactive drop-down menu only has one value
[1]
(b) Any one point from:
– when selecting an option from a finite list
– e.g. choosing an expiry date for a credit card
– navigating between web pages
[1]
(c) Any one point from:
– limited options available
– difficult to find the required option, as only one option is visible
[1]
RAM
ROM
Internal hard drive
Internal modem
–
–
–
–
–
–
–
–
–
–
–
–
–
4
Syllabus
7010
allows random access
stores work user is currently working on
stores files/data temporarily when s/ware running
stores BIOS
stores files/data that should not be changed
main memory of the computer
stores applications software
allows computer to link to a network/internet
allows modulation/demodulation to enable info to be sent/received
by analogue cables
controls the flow of data
error correction
compresses data transmitted
converts digital to analogue and vice versa
[4]
(a) Any two points from:
Real time transaction:
– individual transactions processed as it occurs
– fields/files updated immediately
Batch processing:
– all data collected together before processing started
– processed in one go
– processing often done at night during “quiet periods”
– no need to up date files immediately
[2]
(b) Any one use of batch:
– processing of utility bills (gas, electricity, water, …)
– processing of cheques
– payroll – producing wages/salary slips
Any one use of RTT:
– on line booking of seats in a cinema, flights, …
– any application where double booking must be avoided
[2]
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GCE O LEVEL – October/November 2010
Syllabus
7010
Paper
13
(a) Any two points from:
– consume very little power …
– … hence prolonging internal battery life
– run cool …
– … thus minimising problem of heat dissipation
– no processor fans needed …
– … therefore prolonging internal battery life
– light weight for easier portability
[2]
(b) Any two advantages from:
(1 mark for advantage + 1 mark for expansion)
– very fast transfer/conncetion rate …
– … thus can download/upload files much faster
– always “on” (no need to dial up) …
– … thus don’t have to wait/have instant access to the Internet
– not metered …
– … thus it is possible to download large files without additional cost
– telephone lines not tied up whilst computer in use …
– … this is because broadband uses a wide bandwidth
– because of the high data transfer rate …
– … it is possible to do video conferencing or use VOIP systems
[4]
One mark for each method:
Data collection method
magnetic stripe reader
chip and PIN reader
OR
touch screen
OMR
[3]
7
1 mark for named method, 1 mark for advantage and 1 mark for each disadvantage (these MUST
match up with named method)
Direct:
Advantages:
– less likely to malfunction since fully tested
– immediate benefits/less time wasted
– reduced costs (only one system so no need to duplicate staff)
Disadvantages:
– disastrous if the new systems does fail
Parallel:
Advantages:
– if new system goes down, there is a backup system in place
– possible to gradually train staff/staff have time to get used to the new system
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Syllabus
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Paper
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Phased:
Advantages:
– only a small part of the operation affected if new system fails
– no need to pay for two sets of wages
Disadvantages:
– time consuming (each part needs testing fully before expanding system)
Pilot:
Advantages:
– if new system fails, only that part will be affected
– possible to gradually train staff on pilot before whole system changes over
Disadvantages:
– time consuming (waiting to see how pilot works before rolling out to rest of the organisation)
[6]
8
Any three points from:
– animation effects produced by animator using key frames (which define start point and end
point of a movement e.g. open the mouth)
– use of tweening/morphing (differences in appearance between key frames are calculated
using tweening/morphing)
– use of avars (animation variables)
– successive sets of avars control movement of animated character
– adding of surfaces to avars using rendering (realistic image)
– generation of avars using markers on real moving objects …
– … or using joystick to manually produce stick models
– software prevents need to produce hundreds of hand drawn sketches
[3]
9
(a) 1 mark for each advantage and 1 mark for each disadvantage:
Advantages:
– reaches a larger audience
– people can read information on paper copies at their leisure
– permanent copy which can be referred back to later
Disadvantages:
– need a high quality colour printer
– cost of ink, paper, etc.
– no sound, video, animation or special effects
– need to distribute by hand (time and cost issues)
[4]
(b) 1 mark for each advantage and 1 mark for each disadvantage:
Advantages:
– can be interactive with the presenter
– can have sound, video, animation or special effects
– easier to update (don’t have to re-print or re-distribute)
Disadvantages:
– not a permanent record
– people may not go to the presentation
– need expensive equipment (e.g. projector)
– needs to be set up each time it is used
[4]
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Syllabus
7010
Paper
13
10 (a) Any two points from:
– a program/software/code
– which can replicate itself automatically
– attach themselves to e.g. files
– cause damage to computer system (e.g. delete/change/corrupt data)
[2]
(b) Any two points from:
– data which is jumbled up …
– … to prevent unauthorised people from understanding data
– a key is needed to encrypt data (encryption key)
– a key must be known to decrypt data (decryption key)
– even if data is accessed it can’t be read without necessary key
[2]
(c) (i) Any one point from:
– viruses could be attached to the data and backup copies may still be “infected”
– when copying backup data onto computer may transfer virus again
[1]
(ii) Any one point from:
– encryption only makes data, already accessed, unreadable
– encryption doesn’t stop access to files
[1]
11 (a) (i) range check
(ii) consistency check / crossfield check
(iii) presence check
[3]
(b) 1 mark for name and 1 mark for example. Example must match name
–
–
–
–
Name
Example
type/character check
format check
length check
check digit
only letters typed into name field
ensure date typed in correct format
ensure year field has four digits
on barcodes to ensure they have been read correctly
12 (a) Any two points from:
– use a search engine …
– … and enter KEY words (e.g. CLOUD + COMPUTER)
[2]
[2]
(b) Any two advantages from:
– more likely to be up-to-date
– can contain multimedia files
– more information is available
– can find information anywhere (e.g. away from home)
– usually faster than looking through paper-based information (must be a comparison)
– easier to incorporate information into own work, projects, etc.
[2]
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Syllabus
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(c) Any two disadvantages from:
– not regulated/checked, therefore may be inaccurate/incorrect
– easy to get irrelevant information/sites/overabundance of info
– can download viruses, spyware, etc.
– risk of finding porn sites
– need to invest in computer system + broadband
– sometimes information is withdrawn and is lost from the Internet
[2]
13 (a) = (C2 * 0.02) + (D2 * 0.15)
← 1 mark → ← 1 mark →
[2]
(b) = MAX (E2:E6)
[1]
(c) Any two points from:
–
–
–
new column F added
new formula e.g. F2 = 65 + (800 – D2) * 0.15
modify formula in, e.g. E2, to include (800 – D2) * 0.15
[2]
14 (a) 8
[1]
(b) Hotel Ref
[1]
(c) H41, N15, L44, N21 (-1 for each error or omission)
[2]
(d) (Distance from airport (km) < 10) AND (Price per person($) < 100)
←-------------- 1 mark ---------------→ ←------------- 1 mark --------------→
OR
(Price per person($) < 100) AND (Distance from airport (km) < 10)
←---------- 1 mark ----------→ ←------------------ 1 mark ------------------→
[2]
(e) N15, N21, L44, H41, H30, H21, K22, K14
↑
(last 2 in any order)
[2]
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Page 8
Syllabus
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Paper
13
15 Award marks as shown below
START
Light sensor
detects
movement
No
4
(1 mark)
Yes
2
No
6
(1 mark)
Yes
1
(1 mark)
No
5
7
Yes
(1 mark)
Yes
3
No
1 = check sensor value with stored value
2 = convert signal to digital
3 = has alarm been re-set
4 = is a signal detected?
5 = is sensor value normal?
6 = is signal digital?
7 = sound an alarm
[4]
(b) Any two points from:
– sensor information/signal usually analogue
– computers can only read/understand digital signals
[2]
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Syllabus
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(c) 1 mark for name of sensor + 1 mark for application
Application must match the sensor
Can have the same application for different sensors
Sensor type
Possible applications
(1)
(2)
used in controlling central heating systems
used to control/monitor temperatures in chemical processes
(1)
(2)
monitoring of greenhouse environment
any process where moisture is an issue (e.g. production of tablets
in a pharmaceutical company)
(1)
environment (e.g. measuring oxygen content in a river to check
for pollution)
infra red
(1)
(2)
detecting an intruder by breaking an infra-red beam
counting (e.g. counting coins as each one breaks the beam)
pressure
(1)
(2)
detecting intruders in a burglar alarm system
some systems still use these to count vehicles on the road
acoustic
(1)
(2)
picks up sound (e.g. burglar alarm system)
detecting liquids moving in pipes (chemical processes)
motion
(1)
detecting speed (e.g. radar guns measuring vehicle speed)
(1)
(2)
(3)
used to measure acidity in rivers (pollution monitoring)
used in greenhouses to monitor soil acidity
used to monitor/control chemical process where acidity levels are
important
(1)
these tend to be versions of the above (e.g. light or infra-red)
temperature
moisture
oxygen
pH
proximity/distance
[2]
(d) Any one from:
– DAC (digital to analogue converter)
– actuators
[1]
16 (a) (i)
1
5
1
1
8
5
1
2
3
4
[1]
(ii) more than one person can have same date of birth
[1]
(iii) Any one from:
– give different 4-digit codes to people
– increase the number of digits in code (e.g. 10 instead of 4)
[1]
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1st
3rd
4th
7th
P
U
L
6
Syllabus
7010
Paper
13
[1]
(ii) to prevent illegal access to the website
[1]
(c) Any two from:
– he last logged on on 16th March 2010 and system shows 14th April 2010
– there is evidence of illegal access
17 (a) highest = –100; total = 0: count = 0 (1 mark)
input number
(1 mark)
while number < > –1 do
(1 mark)
total = total + number
(1 mark)
count = count + 1
if number > highest then highest = number
input number
endwhile
average = total/count
(1 mark)
print average, highest
[1]
initialise values NB highest cannot be 0
inputs in the correct place
loop until –1 is input
calculate number total
and count numbers input
(1 mark) highest
calculate average value
and output average and highest value
[4]
(b) d = 0
(1 mark) initialise value
input number
(1 mark) input number and set variable
t = number
to this number
repeat
(1 mark) correct loop
t = t /10
(1 mark) **method to find number of digits
d=d+1
(1 mark) **counting number of digits
until t < 1
print number, d
(1 mark) correct output outside the loop
(** NOTE: there are other ways of finding number of digits e.g.
if number > 0 then d = 1
else if number > 9 then d = 2
……………………………
else if number > 999999 then d = 7 etc.)
If no loop then 0 for loop and 0 for output
[4]
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UNIVERSITY OF CAMBRIDGE INTERNATIONAL EXAMINATIONS
General Certificate of Education Ordinary Level
COMPUTER STUDIES
7010/01
For Examination from 2011
Paper 1
SPECIMEN PAPER
2 hours 30 minutes
READ THESE INSTRUCTIONS FIRST
Attempt all questions using the spaces provided.
Calculators may be used.
Brand names of software will not be regarded as acceptable answers.
This document consists of 16 printed pages and 2 blank pages.
[Turn over
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1
State two desirable properties of processors found in laptop computers.
selected property is desirable.
Explain why the
Property 1
Reason
Property 2
Reason
[4]
2
Weather forecasting using computer models has made predicting weather more accurate.
(a) Describe how data is gathered for the computer model.
[2]
(b) How does the computer model make its prediction based on the new weather data input?
[2]
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(c) Describe two ways the predicted weather for a week could be conveyed to the user.
1
2
[2]
3
Some items of food now have additional bar codes which convey information about how to cook
the food. Special ovens are needed to take advantage of this additional information. If the bar
code is held close to a reader on the front of the oven, the oven will automatically set cooking
times and temperature settings to ensure the perfect meal.
(a) How does the oven ensure that the food is correctly cooked?
[2]
(b) Give two advantages to the user of this new technology.
1
2
[2]
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4
Vehicles are now fitted with satellite navigation systems (GPS) to help them get directions.
(a) How does the system know the exact position of the vehicle?
[2]
(b) The directions are often given verbally. Give one advantage of doing this.
[1]
(c) The satellite navigation systems are known to sometimes give incorrect directions. Give two
reasons why this might happen.
1
2
[2]
5
(a) Give two differences between an intranet and the Internet.
1
2
[2]
(b) Give two reasons why companies allow intranet access rather than Internet access to their
employees.
1
2
[2]
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6
(a) To access the Internet, a computer system requires the user to insert a smart card into a slot
on the side of a keyboard. They then need to type in a PIN. Give two advantages of this
system.
1
2
[2]
(b) Many passports and security cards now contain an induction loop and microchip which
uniquely identifies the item and the user. Give two security advantages of using such a
system.
1
2
[2]
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8
Many mobile phones offer cameras which allow still and movie photos to be taken.
(a) What recent technology has enabled this facility to be offered in mobile phones?
[1]
(b) Describe two ways to download the photo files from the mobile phone to a computer.
1
2
[2]
(c) Access to the Internet is also offered to mobile phone users. Give two advantages of this
technology.
1
2
[2]
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9
The following algorithm inputs 100 numbers and outputs which number is the smallest and which
number is the largest.
10 largest = 0
20 smallest = 0
30 for x = 0 to 100
40
input number
50
if number > largest then largest = number
60
if number < smallest then smallest = number
70
x=x+1
80 next x
90 print largest, smallest
There are three errors in this algorithm. Locate these errors and suggest what changes should
be made to the algorithm.
Error 1
Change 1
Error 2
Change 2
Error 3
Change 3
[6]
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10 Read the following flowchart carefully.
START
A = 0, B = 0, C = 0
X=1
Input N
Is X
N
No
Output A, B, C
STOP
Yes
Input T
Is T > 0
Yes
A=A+1
No
Is T < 0
Yes
B=B+1
No
C=C+1
X=X+1
Draw the trace tables for the following sets of test data
(i)
5, 30, 20, –20, 10, –30
(ii) 8, 0, 0, –10, 5, 20, 0, 0, 0
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(i)
X
N
T
A
B
C
Output
X
N
T
A
B
C
Output
(ii)
[6]
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0
11 Draw the truth table for the following logic network:
A
AND
OR
B
X
OR
AND
C
NOT
A
B
C
1
1
1
1
1
0
1
0
1
1
0
0
0
1
1
0
1
0
0
0
1
0
0
0
X
[4]
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12 Draw a logic network and truth table for the following logic problem:
“A sprinkler (S) is ON if
either temperature alarm (T) is ON and cooler alarm (C) is ON
or vent alarm (V) is OFF and cooler alarm (C) is ON”
Working
Logic network:
Truth table:
T
C
V
1
1
1
1
1
0
1
0
1
1
0
0
0
1
1
0
1
0
0
0
1
0
0
0
S
[9]
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2
13 (a) Many of the portable memory devices available at the moment use either solid state or
miniature hard disk drives. Choose two devices and state which memory type is used and
why it is used.
Device 1
Type of memory
Reason for choice
Device 2
Type of memory
Reason for choice
[6]
(b) New recording systems use hard drives to store movie files. How is it possible to record on
the hard drive at the same time as reading from it?
[2]
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3
(c) Two rival companies offer devices which store music files in a digital format. Music files are
down loaded from the Internet. Give two possible reasons why the music files play back
correctly on one machine but not the other.
1
2
[2]
14 The use of video conferencing has increased considerably in recent years.
(a) Give two effects on companies in adopting video conferencing.
1
2
[2]
(b) Give two social effects of adopting video conferencing.
1
2
[2]
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4
15 Using the Internet it is possible to home in on live images which show aerial photographs of
buildings anywhere on the Earth.
(a) How are the photographs of buildings generated?
[1]
(b) It is possible to have the aerial photograph placed on top of a more traditional road map.
Give an advantage to the user of having this facility.
[1]
(c) Give one additional facility of having online maps available on the Internet.
[1]
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5
16 A system uses 8 digit numbers with an additional eighth digit used as a check digit.
(a) Give two types of error which can be detected using a check digit when transmitting data.
1
2
[2]
(b) Each of the eight digits in the number has a digit position.
e.g.
8 7 6 5 4 3 2 1
3 0 5 5 1 6 2 5
←
←
digit position
digits (digit in position 1 is the check digit)
The validity of the check digit is found using the following calculation:
• multiply each digit by its digit position
• add together the results of the multiplications
• divide the sum by 11
• if the remainder is ZERO then the number is valid
For example, in the above number we have a sum of 110. Dividing by 11 gives a remainder of 0.
Thus the number is valid. For each of the following 8 digit numbers, indicate whether they are
valid or not. Show all working.
(i) 8 1 3 9 1 2 0 7
Working:
Valid number?
(ii) 5 5 0 3 1 6 1 7
Working:
Valid number?
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6
17 Airports put a unique bar code on all luggage to ensure it is loaded on to the correct flight.
(a) What validation check is made on a bar code number?
[1]
(b) Give two pieces of information that could be stored on the file that links to each unique bar
code.
1
2
[2]
(c) Give one advantage of using bar codes in this application.
[1]
(d) Give an example of another application for bar codes.
[1]
18 Many systems are now controlled by microprocessors and sensors.
Name two different sensors which could be used to control the following systems:
Automatic doors
Central heating
[2]
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7
19 The exchange rate between the US Dollar (US$) and the Brazilian Real (R$) changes every day.
Write an algorithm, using pseudocode or otherwise, which inputs the exchange rate for every day
over a 10 year period (assume that each year = 365 days) and then outputs the following:
•
•
•
•
The average (mean) exchange rate
The best (highest) exchange rate
The worst (lowest) exchange rate
The number of occasions when the exchange rate was above 2.0
[6]
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UNIVERSITY OF CAMBRIDGE INTERNATIONAL EXAMINATIONS
General Certificate of Education Ordinary Level
COMPUTER STUDIES
7010/01
For Examination from 2011
Paper 1
SPECIMEN MARK SCHEME
2 hours 30 minutes
MAXIMUM MARK: 100
This document consists of 10 printed pages.
[Turn over
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1
One mark for each property and one mark for each reason:
consume little power ….
…. hence prolonging internal battery life
run cool ….
…. thus minimising problem of heat dissipation
no processor fans required ….
…. therefore prolonging internal battery life
2
[4]
(a) Any two points from:
- sensors collect data from weather stations
- readings from weather stations sent to the weather centre on disk etc.
- readings from other sources (e.g. airline pilots) sent to weather centre
- weather balloons, satellites, etc. send information remotely
[2]
(b) Any two points from:
- system compares known weather patterns/data ….
…. with new data received
- known weather patterns produced from previous data
- carries out a statistical probability calculation of most likely weather
[2]
(c) Any two ways from:
- “weather map” superimposed map of country/area
- can show changes in weather patterns in time (e.g. movement of clouds)
- produces series of figures showing pressures, temperatures, etc.
- produces colour-keyed symbols to show temperature, rainfall, etc.
3
[2]
(a) Any two points from:
- required values stored on embedded microprocessor in the oven
- when barcode read, stored values retrieved ….
…. and are compared to data on the microprocessor
- oven automatically sets timings, temperatures, etc.
[2]
(b) Any two advantages from:
- can’t get it wrong
- no need to set the oven manually (e.g. power settings)
- cooking conditions can be variable – therefore produce ideal cooking environment
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4
(a) Any two points from:
- use of global positioning satellites
- satellites transmit signals to Earth
- car system receives signals from (at least 3) satellites …
- … and calculates position of car
- combines satellite information with stored maps to allow directions
[2]
(b) Any one point from:
- safer – no need to read maps
- allows driver to concentrate on driving
- no need to interpret maps
[1]
(c) Any two reasons from:
- road changed – therefore no longer matches stored maps
- global positioning not sufficiently accurate
- (temporary) loss of signal
5
[2]
(a) Any two difference from:
- (Internet) INTERnational NETwork
- (Intranet) INTernal Restricted Access NETwork
- Intranet only gives local information relevant to, e.g. a company
- can block access to sites outside the company network
- based on a local network, not necessary to have external modems
- information stored on local servers
- Internet can be accessed from anywhere
- Internet available to everyone; intranet requires password entry
- intranet is behind a firewall
- a computer network, based on Internet technology, that is designed to meet the internal
needs for sharing information within a single organisation or company
- an intranet is a web site geared toward use specifically by a company's employees. It will
often contain company or project-specific information that allows employees to coordinate
more efficiently
[2]
(b) Any two reasons from:
- safer since less chance of external hacking or viruses
- can prevent workers accessing unwanted sites
- can ensure information is specific to the company
- easier to send out “sensitive” messages to remain within company only
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6
(a) Any two advantages from:
- more secure since user needs both the card and the PIN to access
- secures online transactions since smart card read directly ….
…. and this contains encryption algorithms etc.
[2]
(b) Any two advantages from:
- passport cannot be copied – reduces fraud
- chip contains personal data which identifies passport owner
- induction loop allows passport to be read by “portal” readers
7
8
[2]
Any five descriptions of systems life cycle stages:
- fact finding (e.g. by way of interviews etc.)
- feasibility study (e.g. cost benefits etc.)
- analysis stage (e.g. analyse company requirements etc.)
- design stage (e.g. determine hardware and software etc.)
- testing strategies (e.g. how to test validation routines etc.)
- user/technical documentation (e.g. technical doc contains algorithms etc.)
- implementation (e.g. immediate changeover etc.)
- evaluation (e.g. feedback on ease of use of new system etc.)
- maintenance (e.g. new hardware added to meet a new need etc.)
[5]
(a) larger memory capacities in smaller space
[1]
(b) Any two ways from:
- send an email/message from phone to computer
- take out the memory card and connect to computer
- connect phone via USB port to computer
[2]
(c) Any two advantages from:
- on the move, can download information on maps etc.
- can readily download bus timetables etc. when away from home
- can access websites while at, e.g., the supermarket doing shopping
9
[2]
One mark for each correct error identified
line 20 – smallest should be set at a high value such as smallest = 100000
line 30 – loop does 101 iterations; should be for x=1 to 100
line 70 – count not required inside for loop; x = x + 1 would corrupt the loop
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10 One mark for correct output, two marks for other two columns being correct
trace tables:
(i)
X
N
T
1
2
3
4
5
6
5
30
20
-20
10
-30
A
0
1
2
B
0
C
0
Output
1
3
2
3, 2, 0
← - - - - - - - - 1 mark - - - - - - →← - - - - - - - - 1 mark - - - - - - →← 1 mk →
[3]
(ii)
X
N
T
1
2
3
4
5
6
7
8
9
8
0
0
-10
5
20
0
0
0
A
0
B
0
C
0
1
2
Output
1
1
2
3
4
5
2, 1, 5
← - - - - - - - - 1 mark - - - - - - →← - - - - - - - - 1 mark - - - - - - →← 1 mk →
[3]
11 One mark per two rows:
Truth table:
A
1
1
1
1
0
0
0
0
B
1
1
0
0
1
1
0
0
C
1
0
1
0
1
0
1
0
X
1
1
0
0
0
1
0
0
[4]
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12 Statement:
Award marks as shown:
S = 1 if [T = 1 AND C = 1] OR [V = NOT 1 AND C = 1]
← - - - - 1 mark - - - - → ← - - - - - 1 mark - - - - - →
[2]
Logic network:
Award one mark per correct gate:
T
AND
OR
S
C
AND
V
NOT
[4]
Truth table:
Award one mark for each row showing correct 1-value in column S:
T
1
1
1
1
0
0
0
0
C
1
1
0
0
1
1
0
0
V
1
0
1
0
1
0
1
0
S
1
1
0
0
0
1
0
0
[3]
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13 (a) One mark per device, one mark for type of memory and one mark for reason;
devices such as:
USB flash memories
MP3/4 players
Cameras
Mobile phones
memories such as:
Solid state
Miniature hard drives
reasons such as:
Hard drives are removable
Solid state – no need for battery back up
[6]
(b) Any two points from:
- use of a read head and write head working independently
- use of data buffers
- reference to special software to allow dual access
[2]
(c) Any two points from:
- different file formats used by the two systems
- protection built into the music files
- file corruption during download
[2]
14 (a) Any two effects from:
- safer to work force since less travelling involved
- much cheaper than paying for transport/accommodation
- changes in communications policies/philosophy
- faster response to issues where many people needed
- less stressed work force (thus more efficient)
- don’t lose staff for several days whilst attending meetings
[2]
(b) Any two effects from:
- less environmental impact (less air travel)
- less travelling (so less stress)/less time away from home
- less social mixing with other personnel from other offices
- loss of “incentive” of foreign travel
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15 (a) use of satellite technology
[1]
(b) Any one from:
- can look for a landmark and then find street/road names
- can see what roads really look like which helps when driving
[1]
(c) Any one from:
- can type in 2 post/zip codes and get journey map
- can see route highlighted on screen maps
[1]
16 (a) One mark per reason
if two digits transposed e.g. 1 5 2 8 instead of 5 1 2 8
if one digit is incorrect e.g. 5 4 2 8 instead of 5 1 2 8
(b) (i) 8 7 6 5 4 3 2 1
8 1 3 9 1 2 0 7
1
mark
sum = 64 + 7 + 18 + 45 +4 + 6 + 7 = 151
}
}
}
}
divide by 11 gives 13 remainder 8
}
1 mark
thus number is not valid
}
1 mark
1
mark
sum = 40 + 35 + 15 + 4 + 18 + 2 + 7 = 121
}
}
}
}
divide by 11 gives 11 remainder 0
}
1 mark
thus number is valid
}
1 mark
(ii) 8 7 6 5 4 3 2 1
5 5 0 3 1 6 1 7
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17 (a) check digit
[1]
(b) Any two points from:
date/time of flight
flight number
weight (in kg) of luggage
destination airport
intermediate airport(s)
passenger name
passenger address
departure terminal/airport
passport number
[2]
(c) Any one advantage from:
- can track whereabouts of luggage
- in case luggage is lost, can locate its history
- easier to ensure correct transfer of luggage if intermediate airport used
[1]
(d) Any one from:
supermarkets
smart ovens
[1]
18 One mark per sensor
automatic doors – infra red sensors
central heating – temperature sensors
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0
19 Award marks as shown up to the maximum of 6 marks
best = 0
worst = 100
} 1 mark
total = sum = 0
for x = 1 to 3650
} 1 mark
input xchangerate
} 1 mark
if xchangerate > best then best = xchangerate
} 1 mark
if xchangerate < worst then worst = xchangerate
} 1 mark
if xchangerate > 2 then total = total + 1
} 1 mark
sum = sum + xchangerate
next x
avge = sum/3650
} 1 mark
output best, worst, total, avge
} 1 mark
marking points:
correct initialisation
correct loop and loop control
correct input (inside loop)
check on best and worst exchange rates
counting number of occasions when rate exceeded 2.0
finding the average value (sum inside loop and calc)
correct outputs (all outputs AND outside loop)
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1 mark
1 mark
2 marks
1 mark
1 mark
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UNIVERSITY OF CAMBRIDGE INTERNATIONAL EXAMINATIONS
General Certificate of Education Ordinary Level
*0958480891*
7010/11
COMPUTER STUDIES
May/June 2011
Paper 1
2 hours 30 minutes
Candidates answer on the Question Paper.
No Additional Materials are required.
READ THESE INSTRUCTIONS FIRST
Write your Centre number, candidate number and name on all the work you hand in.
Write in dark blue or black pen.
You may use a soft pencil for any diagrams, graphs or rough working.
Do not use staples, paper clips, highlighters, glue or correction fluid.
DO NOT WRITE IN ANY BARCODES.
Answer all questions.
No marks will be awarded for using brand names of software packages or hardware.
At the end of the examination, fasten all your work securely together.
The number of marks is given in brackets [ ] at the end of each question or part question.
For Examiner's Use
This document consists of 24 printed pages.
IB11 06_7010_11/FP
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1
Give three tasks carried out by an operating system.
For
Examiner's
Use
1
2
3
[3]
2
A user decides to use an Internet search engine to help locate a hotel.
(a) What is a search engine?
[1]
(b) Give two possible problems the user might encounter when using a search engine.
1
2
[2]
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(c) The search engine found the website of a suitable hotel.
For
Examiner's
Use
Give three features you would expect to see on a hotel website.
1
2
3
[3]
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3
A worker at a company has to go through a logon procedure to gain access to her computer
system.
(a) The first thing she has to do is type in a user name and a password.
Why is this done?
[1]
(b) The password is typed in twice.
Why is this done?
[1]
A menu then appears on her screen. She chooses to connect to the Internet.
(c) Describe two ways her computer system is protected against loss or corruption of files
once the computer system is connected to the Internet.
1
2
[2]
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Use
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178
(d) The worker leaves her computer system for a 10-minute break.
For
Examiner's
Use
(i) From a health and safety aspect, why does she need to take a regular break?
(ii) Apart from switching off her machine, how could she ensure her computer system
was secure whilst taking her regular break?
[2]
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4
The following diagram shows a typical expert system.
Explanation
System
W
For
Examiner's
Use
Working
store
X
Z
Knowledge
Base Editor
Y
(a) Name the missing labels W to Z using the following list of possible options.
Inference Engine
Expert System Shell
Knowledge Base
User Interface
W
X
Y
Z
[4]
(b) Name one of the components that makes up the knowledge base.
[1]
(c) Give one advantage and one disadvantage of using expert systems.
Advantage:
Disadvantage:
[2]
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(d) Name two examples of the use of expert systems.
For
Examiner's
Use
1
2
[2]
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5
Study the following flowchart very carefully:
For
Examiner's
Use
START
count = 1
total = 0
X=0
INPUT
number
Is number > 0 ?
Yes
total = total + number
X=X+1
No
count = count + 1
Yes
Is count <= 10 ?
No
average = total/X
OUTPUT
average
STOP
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(a) Complete the trace table for the following data set:
15,
-2,
0,
count
8,
0,
number
21,
-8,
total
-12,
1,
X
For
Examiner's
Use
25
average
OUTPUT
[4]
(b) What is the purpose of this flowchart?
[1]
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0
6
Describe the role of computer software and hardware when producing animation effects in
the television and film industry.
[3]
7
A spreadsheet has been set up to compare the costs of types of fruit juice sold by a shop.
1
2
3
4
5
6
7
A
NAME OF FRUIT
JUICE
Apple
Orange
Pomegranate
Caju
Mango
B
NORMAL PRICE
PER BOTTLE ($)
3.50
2.80
4.55
2.00
1.05
C
D
VOLUME OF
COST PER LITRE
BOTTLE (LITRES)
($)
1.0
3.50
1.0
2.80
0.7
6.50
2.0
1.00
0.7
1.50
Average cost:
3.06
(a) (i) What formula is in cell D5 to calculate the cost of Caju juice per litre?
(ii) What formula is in cell D7 to calculate the mean (average) cost of fruit juice per
litre?
[2]
(b) What validation check could be carried out on the data in cells B2 to B6?
[1]
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Use
.
184
(c) Three extra columns are to be added to this spreadsheet:
Column E will show a percent discount on the normal price of a bottle of fruit juice
(as shown in column B);
Column F will show this discount in dollars ($);
Column G will show the price of a bottle of fruit juice after discount.
For
Examiner's
Use
Complete the spreadsheet by showing the formulas that need to be placed in cells
F2 to F6 and G2 to G6.
1
E
Percentage
discount (%)
2
10
3
20
4
15
5
10
6
5
F
Discount amount ($)
G
Discounted price per
bottle ($)
[4]
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2
8
Many computer-controlled systems use sensors to gather physical data. For example,
temperature sensors are used in the control of central heating systems.
(a) Name three other sensors and give a different application for each named sensor.
Sensor 1:
Application:
Sensor 2:
Application:
Sensor 3:
Application:
[6]
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Examiner's
Use
.
186
3
(b) Describe how temperature sensors are used in computer-controlled central heating
systems.
For
Examiner's
Use
[3]
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4
9
An international company uses video-conferencing. The system is set up as follows:
For
Examiner's
Use
screen + web cam
microphone
microphone
speakers
conference room 1
(
conference room 2
represents a person at the meeting)
(a) Describe how the video-conferencing system works.
[4]
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5
(b) Give two reasons why video-conferencing is gaining in popularity.
For
Examiner's
Use
1
2
[2]
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6
10 (a) Two logic gates are the AND gate and the OR gate. Complete the truth tables for
these two gates:
OR gate
AND gate
A
B
0
For
Examiner's
Use
X
A
B
0
0
0
0
1
0
1
1
0
1
0
1
1
1
1
X
[2]
(b) Complete the truth table for the following logic circuit:
A
AND
OR
B
X
AND
C
NOT
A
B
C
0
0
0
0
0
1
0
1
0
0
1
1
1
0
0
1
0
1
1
1
0
1
1
1
X
[4]
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7
11 (a) Describe three features you would expect to find in a Computer Aided Design (CAD)
package.
For
Examiner's
Use
1
2
3
[3]
(b) Give three different applications where CAD might be used.
1
2
3
[3]
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8
12 Many vehicles use Global Positioning Systems (GPS) to know their exact location at all
times.
(a) How does GPS work?
[3]
A taxi company uses GPS in all its vehicles.
(b) One of its taxis is on Main Street and needs to go to Railway Street.
How is GPS technology used to help the taxi driver get to his new destination?
[2]
(c) Name one other feature of GPS that could be useful to the driver.
[1]
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Examiner's
Use
.
192
9
(d) Give two reasons why the GPS could take the driver to the wrong destination or cause
error messages.
For
Examiner's
Use
1
2
[2]
13 It has been decided to model the traffic flow at a busy road junction.
(a) Describe how data is gathered for this model.
[3]
(b) Give two reasons why a model is used.
1
2
[2]
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0
14 (a) Name and draw two common types of network topology.
Type 1:
For
Examiner's
Use
Type 2:
[2]
(b) Give two advantages of networking computers.
1
2
[2]
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15 A database showing the population of world cities has been produced. A section of the
database is shown below.
Ref
No
1
2
3
4
5
6
7
8
9
10
Name of
City
Tokyo
New York
Sao Paulo
Seoul
Mexico City
Osaka
Manila
Mumbai
Jakarta
Calcutta
Country
Area
Japan
USA
Brazil
S Korea
Mexico
Japan
Philippines
India
Indonesia
India
Asia
America
America
Asia
America
Asia
Asia
Asia
Asia
Asia
City
Population (m)
33.2
17.8
17.7
17.5
17.4
16.4
14.8
14.4
14.3
12.7
For
Examiner's
Use
Urban
Capital
Population (m)
34.1
Yes
21.9
No
20.2
No
22.3
Yes
22.7
Yes
16.8
No
14.9
Yes
19.7
No
17.2
Yes
15.6
No
(a) How many records are shown above?
[1]
(b) Using Ref No only, which records would be found if the following search condition was
typed in
(Country = “India” OR Area = “America”) AND (Capital = “No”)
[2]
(c) Write a search condition to find the cities in Asia with a city population greater than
17 million OR an urban population greater than 20 million.
[2]
(d) Give one advantage of using Y or N rather than Yes or No in the Capital column.
[1]
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2
16 A floor turtle can use the following instructions:
For
Examiner's
Use
Instruction
Meaning
FORWARD d
Move d cm forward
BACKWARD d
Move d cm backward
LEFT t
Turn left t degrees
RIGHT t
Turn right t degrees
REPEAT n
Repeat the next set of instructions n times
ENDREPEAT
End of REPEAT loop
PENUP
Raise the pen
PENDOWN
Lower the pen
(Each square in the drawing below is 10 cm by 10 cm.)
Start
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3
Complete the set of instructions to draw the above shape (shown in bold lines).
For
Examiner's
Use
PENDOWN
LEFT 90
REPEAT
[5]
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4
17 Daniel lives in Italy and travels to Mexico, India and New Zealand. The times differences
are:
Country
Mexico
India
New Zealand
Hours
-7
+4
+11
For
Examiner's
Use
Minutes
0
+30
0
Thus, if it is 10:15 in Italy it will be 14:45 in India.
(a) Write an algorithm, using pseudocode or otherwise, which:
•
•
•
•
Inputs the name of the country
Inputs the time in Italy in hours (H) and minutes (M)
Calculates the time in the country input using the data from the table
Outputs the country and the time in hours and minutes
[4]
(b) Describe, with examples, two sets of test data you would use to test your algorithm.
1
2
[2]
Permission to reproduce items where third party owned material protected by copyright is included has been sought and cleared where possible. Every
reasonable effort has been made by the publisher (UCLES) to trace copyright holders, but if any items requiring clearance have unwittingly been included, the
publisher will be pleased to make amends at the earliest possible opportunity.
University of Cambridge International Examinations is part of the Cambridge Assessment Group. Cambridge Assessment is the brand name of University of
Cambridge Local Examinations Syndicate (UCLES), which is itself a department of the University of Cambridge.
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UNIVERSITY OF CAMBRIDGE INTERNATIONAL EXAMINATIONS
GCE Ordinary Level
MARK SCHEME for the May/June 2011 question paper
for the guidance of teachers
7010 COMPUTER STUDIES
7010/11
Paper 1, maximum raw mark 100
This mark scheme is published as an aid to teachers and candidates, to indicate the requirements of
the examination. It shows the basis on which Examiners were instructed to award marks. It does not
indicate the details of the discussions that took place at an Examiners’ meeting before marking began,
which would have considered the acceptability of alternative answers.
Mark schemes must be read in conjunction with the question papers and the report on the
examination.
• Cambridge will not enter into discussions or correspondence in connection with these mark schemes.
Cambridge is publishing the mark schemes for the May/June 2011 question papers for most IGCSE,
GCE Advanced Level and Advanced Subsidiary Level syllabuses and some Ordinary Level
syllabuses.
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Syllabus
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Paper
11
Any three from:
– handling interrupts
– input/output/peripheral/device control
– spooling
– multitasking/JCL/batch processing
– multiprogramming
– user interface
– load/run software
– processor management/task management
– file (copy/save/delete etc) management
– memory management
– user accounts
– utility tasks (defrag, format etc.)
– error reporting/handling
– security management
– power management
[3]
(a) Any one point from:
– program searches documents for key words/query and returns a list
– software that searches for sites based on words input
– use their own database to locate data defined by key words/query input
[1]
(b) Any two points from:
– too wide a search/too much information/irrelevant information found
– “unwanted”/undesirable sites found during the search
– picks up words with same spelling but different meaning
– search engine loyalty/funded by advertising puts websites top of list
– may produce out of date sites
– misleading/incorrect information
[2]
(c) Any three features from:
– shopping basket
– checkout
– secure credit card payment
– hyperlinks to other sites
– drop down boxes/calendar with available dates
– virtual tour of the hotel/hotel facilities
– currency conversions
– interactive map/directions to hotel/contact details
– drop down boxes with room rates
– confirmation by email/textmessage
– form to fill in customer details/booking form
– special offers
[3]
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3
Paper
11
(a) Any one from:
–
–
–
prevents unauthorised access to files/the computer system
access to her own directories
allow authorised access
[1]
(b) Any one from:
– verification check
– (double check) password is correct
[1]
(c) Any two from:
– firewall
– anti-virus software
– (automatic) backup of data
– auto-save
[2]
(d) (i)
4
Syllabus
7010
Any one from:
– repetitive strain injury (RSI) / pain in wrist/fingers
– carpal tunnel syndrome
– headaches/eyestrain/back ache/neck ache
[1]
(ii) Any one from:
– “lock” computer system
– automatic screen saver (after short time of inactivity)
– log off from the system
– if computer in an office, lock the office door
[1]
(a) W = User Interface
X = Inference Engine
Y = Expert System Shell
Z = Knowledge Base
[4]
(b) Any one from:
– Facts
– Rules Base
[1]
(c) Any one advantage from:
– reduces the time taken to solve a problem
– can predict future faults
– can lower wage bills (less skilled work force needed)
– can be used in countries where the necessary skills are rare
– can have access 24/7
– less likely to miss a question
Any one disadvantage from:
– expensive system to set up/purchase
– necessary to do training on the new system
– must be kept up-to-date
[2]
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Syllabus
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Paper
11
(d) Any two examples from: e.g.
– medical diagnosis
– diagnostics with example (car engine faults, electronic components)
– tax/financial calculations
– chess
– mineral/oil prospecting
– animal/plant classification
5
6
7
(a)
count
1
2
3
4
5
6
7
8
9
10
11
number
15
–2
0
8
0
21
–8
–12
1
25
total
0
15
x
0
1
23
2
44
3
45
70
4
5
average
14
OUTPUT
[2]
}
}
}
1
1
1
}1
14
<- - - - - - 1 mark - - - - - - - ->< - 1 mark ->< - 1 mark ->< - - - - - - - - 1 mark - - - - - - - - ->
[4]
(b) Find the average of all positive numbers entered
[1]
Any three points from:
– computer s/ware helps produce more realism
– ability to “move” mouth properly to accurately mimic speech
– can store frames straight to dvd (or similar)
– speeds up/simplifies editing process
– removes need for several artists to draw the animations
– use of tweening speeds up the process
– reference to morphing
– reference to avatars
– reference to avars (animation variables)
– reference to rendering
[3]
(a) (i) = B5/C5
[1]
(ii)
= (D2 + D3 + D4 + D5 + D6)/5
= AVERAGE(D2:D6)
= SUM(D2:D6)/5
OR
OR
[1]
(b) Any one from:
– character/type check
– range check
– format check
[1]
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Syllabus
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Paper
11
(c)
1
2
3
4
5
6
E
Percent
discount
(%)
10
20
15
10
5
F
Discount
amount
($)
= B2 * E2/100
= B3 * E3/100
= B4 * E4/100
= B5 * E5/100
= B6 * E6/100
G
Discounted price
per bottle ($)
= B2 – F2
= B3 – F3
= B4 – F4
= B5 – F5
= B6 – F6
NOTE: 1 mark for first formula in F2
1 mark for replication of formula in F3 through to F6
1 mark for first formula in G2
1 mark for replication of formula in G3 through to G6
[4]
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Syllabus
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Paper
11
(a) 1 mark for naming the sensor + 1 mark for correct application of named sensor
(applications MUST be different)
Named
sensor
Humidity
Moisture
(water)
oxygen
light
infra red
pressure
gas
Application of named sensor
greenhouse environmental control
spin drier in automatic washing machine
libraries/archives where moisture levels need
controlling
fish tank/aquarium
environmental monitoring
car engine management system/fuel injection
system
burglar alarm
automatic doors
greenhouse environmental control
automatic doors
car in correct place to allow paint spraying in car
factory
burglar alarm
traffic control
automatic doors
burglar alarm
Environmental monitoring
Safety system
[6]
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Syllabus
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Paper
11
(b) Any three points from:
–
–
–
–
–
–
–
sensor relays reading back to computer
if reading is analogue, need an analogue to digital converter (ADC)
computer compares reading with stored value
sends signal to actuators
signal converted using digital to analogue converter (DAC)
actuator alters factors such as heating, coolers, etc.
cycle continues / output affects input
accept a diagram such as:
sensors
ADC
computer
DAC
actuator
Central
heating
devices
[3]
How to mark a diagram:
1 mark for link between sensor(s) and computer
1 mark for showing an ADC
1 mark for showing a DAC
1 mark for link from computer to actuator
1 mark for arrow implying cycling of system
9
(a) Any four points from:
–
–
–
–
–
–
–
–
each “conference room” needs to log into system
delegates speak into microphone
webcam takes video image
uses Internet/WAN/broadband/modem to transmit data
use of compression software for video/audio
use of CODEC (which converts and compresses analogue data into digital data
and sends over digital links)
echo cancellation software (allows talking in real time/keeps everything in sync)
video images seen (on screen)/audio heard (using speakers) in real time
(b) Any two points from:
– faster communications now available (e.g. high speed broadband)
– safety reasons (e.g. risk of terrorism attacks on flights)
– costs (saves on overseas travelling/hotel costs)
– cheaper equipment costs
[2]
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Page 8
10 (a)
AND gate
A
0
0
1
1
B
0
1
0
1
OR gate
A
0
0
1
1
X
0
0
0
1
Syllabus
7010
B
0
1
0
1
Paper
11
X
0
1
1
1
(1 mark for correct X column in each gate)
[2]
(b)
A
0
0
0
0
1
1
1
1
B
0
0
1
1
0
0
1
1
C
0
1
0
1
0
1
0
1
X
0
0
1
0
0
0
1
1
}
}
}
}
1
1
1
1
[4]
11 (a) Any three features from: e.g.
– rotate, enlarge, change colour etc.
– costings
– library of parts
– validation of design against specification
– ability to do 2D/3D designs
– link into CAM
– create engineering drawings from solid models
– calculate/test mass, stress etc. in new designs
– electronic component packing
[3]
(b) Any three from: e.g.
– architecture (houses, office blocks, etc.)
– engineering (bridges, roads, etc.)
– interior design (kitchens, bathrooms, etc.)
– water supply/sewer systems
– aerospace
– car (vehicle) design
– chemical/nuclear plant design
– factory layouts
– consumer goods design (e.g. mobile phones)
– ship building
– fashion design
– design of electronic components
[3]
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Paper
11
12 (a) Any three points from:
– satellites transmit signals to sat nav computer
– computer receives/interprets these signals
– system depends on very accurate timing/use of atomic clocks
– each satellite transmits data including location and time
– computer in taxi calculates its position based on at least 3 satellites
– at least 24 satellites in operation at a given time
– position of vehicle is within 1 metre
– refer to triangulation:
satellite 1
satellite 2
Exact
location
of vehicle
satellite 3
[3]
(b) Any two points from:
– maps stored in sat nav memory
– shows directions on a screen
– voice output gives driver directions/instructions
– plots route in advance
– GPS knows exactly where vehicle is
– recalculates route if driver makes a mistake
[2]
(c) Any one point from:
– can estimate time of arrival
– can warn of speed cameras (etc.)
– can warn of road works/diversions/traffic congestion
– can warn if exceeding speed limit
– can give fastest/most scenic route etc.
– can give location of petrol station/hotel etc
[1]
(d) Any two reasons from:
– wrong/outdated maps stored on system
– inaccurate timing
– (temporary) loss of signal
– incorrect start point/end point selected/keyed in
– road works/accident have closed the “expected” route
[2]
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Syllabus
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Paper
11
13 (a) Any three points from:
– collect data at different times of the day
– data collected by filling in paper records
– can use hand held devices to collect data
– use of sensors to collect data
– time how long it takes for vehicle to cross junction
– count number of vehicles in all directions
[3]
(b) Any two points from:
– much safer (if errors made in real life, could be fatal)
– less costly (can try out things first on the model) NEED REASON
– able to test out various scenarios first
– can optimise timings of lights etc. at junctions
– model can be applied to other junctions
– much quicker than doing the real thing
[2]
14 (a) 1 mark for name + correct drawing of each type of network
ring
star
bus
[2]
(b) Any two advantages from:
– sharing of resources (hardware and software)
– easier to communicate computer to computer
– central database – thus all users share same information
– easier to control what users can do (e.g. block Internet access)
– can work from any station and access data
[2]
15 (a) 10
[1]
(b) 2, 3, 8, 10
1 mark per two correct records
Loose 1 mark for each additional record
[2]
(c) (Area = “Asia”) AND (City Population(m) > 17 OR Urban Population(m) > 20)
<- - - - 1 mark - - - -> < - - - - - - - - - - - - - - - - 1 mark - - - - - - - - - - - - -- - - - - ->
OR
(Area = “Asia” AND City Population(m) > 17) OR (Area = “Asia” AND Urban Population(m) > 20)
< - - - - - - - - - - - - - - -1 mark - - - - - - - - - -- - - - -> < - - - - -- - - - - - - - - - 1 mark - - - -- - - - - - - - - ->
[2]
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Syllabus
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Paper
11
(d) Any one advantage from:
– less likely for entry/typing errors
– uses less memory to store records
– faster data entry
16 PENDOWN
LEFT 90
REPEAT 3
FORWARD 30
RIGHT 90
------------------------------------------------------------------------------------------ENDREPEAT
FORWARD 10
LEFT 90
OR
PENUP
------------------------------------------------------------------------------------------PENUP
OR
LEFT 90
FORWARD 10
PENDOWN
------------------------------------------------------------------------------------------REPEAT 2
OR
REPEAT 3
FORWARD 20
------------------------------------------------------------------------------------------RIGHT 90
ENDREPEAT
FORWARD 20
OR
(LEFT/RIGHT 180)
(LEFT 90)
[1]
1 mark
1 mark
1 mark
1 mark
1 mark
Give a mark for each correct group of statements
Alternative answer for last 2 marks:
FORWARD 20
RIGHT 90
------------------------------------------------------------------------------------------FORWARD 20
RIGHT 90
FORWARD 20
[5]
1 mark
1 mark
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11
17 (a) input name$
input H, M
if name$ = “Mexico” then H = H – 7
else if name$ = “India” then H = H + 4: M = M + 30
else if name$ = “New Zealand” then H = H + 11
else print “error”
print H, M
Marking points
– 1 mark for two inputs for country and hours/mins
– 1 mark for check on Mexico
– 1 mark for check on New Zealand
– 1 mark for check on India
– 1 mark for error check
– 1 mark for output in correct place
[4]
(b) Any two sets of test data from:
Normal hours: (hours which do not change the day) e.g. 8
hours which change the day (e.g.. 13 + country = New Zealand)
Normal minutes (which do not change the hour) eg.25
minutes which change the hour (e.g. 40 + country=India)
[2]
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Candidate Name
Centre Number
Candidate Number
UNIVERSITY OF CAMBRIDGE INTERNATIONAL
EXAMINATIONS
General Certificate of Education Ordinary Level
7010/12
COMPUTER STUDIES
Paper 1
May/June 2011
TIME: 2 hours 30 minutes
SUITABLE FOR VISUALLY IMPAIRED CANDIDATES
Candidates answer on the Question Paper.
No Additional Materials are required.
READ INSTRUCTIONS OVERLEAF
The whole of this paper is © UCLES 2011.
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READ THESE INSTRUCTIONS FIRST
Write your Centre number, candidate number and name
on all the work you hand in.
Write in dark blue or black pen.
You may use a soft pencil for any diagrams, graphs or
rough working.
Do not use staples, paper clips, highlighters, glue or
correction fluid.
DO NOT WRITE IN ANY BARCODES.
Answer ALL questions.
No marks will be awarded for using brand names of
software packages or hardware.
At the end of the examination, fasten all your work
securely together.
The number of marks is given in brackets [ ] at the end
of each question or part question.
2
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1
(a) Give TWO features you would expect to find in a
data protection act.
1
2
[2]
(b) Why would this act still not necessarily protect
data stored in a computer system?
[2]
4
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3
Most operating systems provide a user interface.
(a) User interfaces can be either command line
interfaces (CLI) or graphical user interfaces (GUI).
Give ONE advantage and ONE disadvantage of
both types of interface.
Advantage CLI:
Disadvantage CLI:
Advantage GUI:
Disadvantage GUI:
[4]
7
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(b) Give THREE other tasks carried out by an
operating system.
1
2
3
[3]
8
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4
A company has decided to introduce an intranet and
remove Internet access for its staff.
(a) Describe TWO reasons why the company will not
allow its staff Internet access.
1
2
[2]
(b) Apart from removing Internet access, give TWO
advantages to the company of using an intranet.
1
2
[2]
9
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5
The following table shows FOUR applications which
require specialist INPUT devices.
For EACH application, suggest ONE possible INPUT
device and give a reason for your choice.
10
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APPLICATION
INPUT
DEVICE
REASON FOR CHOICE
OF DEVICE
Virtual reality
application
Disabled
person
communicating
with a
computer
system
Automatic
stock control
system at a
supermarket
Information
kiosk at an
airport using a
GUI interface
[8]
11
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6
FIVE security or data loss issues are shown on the left
hand side.
FIVE possible methods of data recovery or protection
are shown on the right.
Match the definitions/descriptions on the left to the
most appropriate method on the right by drawing
connecting arrows.
12
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ISSUES
METHODS
Data loss caused by hard
disk head crash
Anti-virus
software
Hacking into files and
changing or deleting data
Encryption
Introduction of software
that self-replicates and
can cause data loss
Anti-spyware
software
Reading of illegally
accessed documents
Make back-up
files
Software that logs/records
all key presses on your
computer without you
knowing
Use of
passwords
and a firewall
[5]
13
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7
(a) Read the following section of code that inputs
twenty (20) numbers and then outputs the largest
number input.
1
2
3
4
5
6
7
8
h=0
c=0
REPEAT
READ x
IF x > h THEN x = h
c=c+1
PRINT h
UNTIL c < 20
There are THREE errors in this code.
Locate these errors and suggest a corrected piece
of code.
1
2
3
[3]
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(b) The above code is an example of a high-level
language.
Give TWO features of a high-level language.
1
2
[2]
(c) The code is to be interpreted rather than compiled.
Give ONE difference between these two methods.
[1]
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8
A media sales company has set up a website.
The opening page is:
DVD media sales company
Please input your Customer ID
Select your film category
COMEDY
END
(a) (i)
CONTINUE
What TYPE of menu is being used for the film
category?
(ii) Give ONE advantage of this type of menu.
[2]
16
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(b) (i)
Name a validation check that could be used on
the Customer ID field?
[1]
(ii) Describe TWO types of test data, together with
examples, that could be used to see whether
the validation check named in (i) works.
Type 1
Example
Type 2
Example
[4]
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9
Juan decided to buy 40 tracks online from a music
distribution company.
The tracks are all in MP3 format.
(a) What is the benefit of downloading tracks in MP3
format rather than in the normal CD format?
[1]
Juan uses a company which offers the following
Internet broadband transfer rates:
•
•
56 megabits per second DOWNLOAD
16 megabits per second UPLOAD
(b) If each music track is 3.5 megabytes in size, how
long would it take Juan to download his 40 tracks?
(Show your working.)
[2]
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(c) He has decided to upload 36 photographs onto his
social networking website. Each photograph is
1.8 megabytes in size.
How long would it take to upload his photographs?
[2]
19
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10 The following flowchart inputs ten temperatures and
outputs the average (mean) temperature and the
number of temperatures which were negative (i.e. < 0).
START
N=0
sum = 0
X=0
count = 1
input T
X=X+1
sum = sum + T
Yes
is T < 0 ?
N=N+1
No
count = count + 1
Yes
No
is count < 11 ?
average = sum/X
output
average, N
STOP
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(a) Complete the trace table for this flowchart using
the following test data:
5,
N
11, 16, -4, -10, 8, 10, -3, 17, 10
sum
X
count
T
average
[6]
(b) What values are output from the flowchart using
the above test data?
[1]
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11 (a) (i)
Complete the truth table for the following logic
circuit:
A
NAND
NAND
B
C
NAND
A
B
0
0
0
1
1
0
1
1
C
[2]
(ii) Which single logic gate has the SAME function
as the above logic circuit?
[1]
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(b) (i)
Complete the truth table for the following logic
circuit:
A
NOR
NOR
B
C
NOR
A
B
0
0
0
1
1
0
1
1
C
[2]
(ii) Which single logic gate has the SAME function
as the above logic circuit?
[1]
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12 An electronic chess board is connected to a
computer. There are sensors under EACH square and
EACH chess piece has a magnet in its base.
In a game, one player is the computer and the other
player a person.
In the example below, a piece has been moved FROM
A7 TO B5.
Each chess piece has pre-programmed legal moves.
A B C D E
F G H
8
7
6
5
4
3
2
1
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(a) Describe how the computer knows when or if a
chess piece has moved.
[3]
(b) A person moves a chess piece when prompted by
the computer. How would the computer know if
the move made was legal?
[2]
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(c) Name the type of software application that can play
chess games in this way.
[1]
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13 Describe THREE ADVANTAGES and TWO
DISADVANTAGES to the general public of using the
Internet to do online shopping.
ADVANTAGES
1
2
3
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DISADVANTAGES
1
2
[5]
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14 A spreadsheet has been set up to show the size of
some model cars.
A
B
C
D
E
FULL
SCALE
IS MODEL
1
NAME
LENGTH SCALE LENGTH
> 0.25 M ?
(M)
(M)
2 Raudi R8
5.22
18
0.29
3 Monda Civil
4.30
43
0.10
4 R Skate
6.12
18
0.34
5 Silly for 2
2.76
12
0.23
6 Citron C1
3.42
18
0.19
7 Singer S2
5.20
10
0.52
8
(a) What formulas must be in column D?
1
D
SCALE LENGTH (M)
2
3
4
5
6
7
8
[2]
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(b) (i)
The formula = IF (D2 > 0.25, “Y”, “N”) was
typed into E2. What output would be shown in
E2?
(ii) If this formula was replicated all the way down
from E3 to E7, what formula would be in E7?
[2]
(c) Describe a way of filtering out only those models
which are scale 18.
[2]
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15 Name THREE different types of storage media and
give an example of each.
Type 1
Example
Type 2
Example
Type 3
Example
[3]
32
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16 A book shop uses barcodes for its computerised
stock control.
Each book title has a barcode which identifies it.
The data is stored in a table.
(a) A sample of the data stored in the table is shown
below:
BARCODE
BOOK
TITLE
123456789012 Blue
Lagoon
345678901234 Happy
Hour
567890123456 Young
Blood
(i)
AUTHOR COPIES PUBLICATION
DATE
AA
27
10/2001
Smith
BJ
30
11/1997
Cocktail
CM Vein
19
06/2009
Which is the key field?
33
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(ii) Give TWO examples of when the data in the
table will need to be changed.
1
2
[3]
(b) Each barcode has a check digit.
(i)
Explain how the check digit is used as a
validation check.
(ii) What type of error can the check digit identify?
[2]
34
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(c) Name DIFFERENT suitable validation checks for
EACH of the following fields:
Book title:
Copies:
Publication date:
[3]
35
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17 A school has 1800 students. The start date and
leaving date for each student is stored on file. Dates
are in the format YYMMDD (e.g. a student starting on
10th September 2007 and leaving on 4th August 2012
has the data 070910 and 120804 on file).
(a) Write an algorithm, using pseudocode or
otherwise, which
•
•
•
•
•
inputs Student ID for all 1800 students
inputs the start date and leaving date for each
student
carries out a check to ensure the second date
is later
if error, increments error counter
outputs the number of errors
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[5]
(b) Describe, with examples, TWO sets of test data
you would use to test your algorithm.
[2]
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UNIVERSITY OF CAMBRIDGE INTERNATIONAL EXAMINATIONS
GCE Ordinary Level
MARK SCHEME for the May/June 2011 question paper
for the guidance of teachers
7010 COMPUTER STUDIES
7010/12
Paper 1, maximum raw mark 100
This mark scheme is published as an aid to teachers and candidates, to indicate the requirements of
the examination. It shows the basis on which Examiners were instructed to award marks. It does not
indicate the details of the discussions that took place at an Examiners’ meeting before marking began,
which would have considered the acceptability of alternative answers.
Mark schemes must be read in conjunction with the question papers and the report on the
examination.
• Cambridge will not enter into discussions or correspondence in connection with these mark schemes.
Cambridge is publishing the mark schemes for the May/June 2011 question papers for most IGCSE,
GCE Advanced Level and Advanced Subsidiary Level syllabuses and some Ordinary Level
syllabuses.
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GCE O LEVEL – May/June 2011
Syllabus
7010
Paper
12
(a) Any two from:
– data must be up-to-date
– data can only be read/used for the purpose for which it was collected
– data must be accurate/relevant
– data must be deleted/destroyed when no longer needed/don’t keep longer than
necessary
– data must be secure
– data user must register (what data is held)
– data must be used/collected fairly and lawfully
– data must be protected from accidental damage
– only authorised people can have access to the data
– fines will be imposed for data mis-use
– data should not be passed on to 3rd parties without owner’s permission
– person can view data and have it changed if necessary
– safe harbour
[2]
(b) Any two from:
– risk of viruses
– risk of hacking still exists
– (physical) corruption of data (e.g. by using incorrect shutdown procedure)
– theft/loss of CDs/DVDs/memory sticks containing information
– data protection act doesn’t protect the data itself
[2]
(a) Any one from:
– helps users to understand how to use the software package
– instructions on how to operate the system
[1]
Don’t credit candidates who rewrite the question
(b) Any three from:
– how to run/load/install the software package
– how to save a file
– how to search for information
– how to sort the data
– how to print out documents
– how to add/delete/amend records
– purpose of the system/programs/software
– (input) screen layout
– (output) print layouts
– hardware requirements
– software requirements
– sample runs
– error handling/meaning of error messages
– troubleshooting guide
– how to log in/out/shutdown/startup
– tutorials
– backup
– input methods
NOT help
[3]
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Mark Scheme: Teacher version
GCE O LEVEL – May/June 2011
Syllabus
7010
Paper
12
(c) (i) Any one from:
– can ask a team of experts about the problem directly/expand on questions
– links built into the software
– useful if user doesn’t understand problem/has no IT or computing skills
– no need to print out large user manuals (saves money)
– much easier to update if changes made to software
– more customer friendly (leads to repeat business)
(ii) Any one from:
– only available when connected to the Internet
– may take a while to get a response to their query
3
[1]
[1]
(a) Any one advantage of CLI from:
– direct communication with computer system
– not restricted to a number of pre-determined options
– simple interface using keyboard only
– faster response
Any one disadvantage of CLI from:
– need to learn a number of/long/complex commands
– need to type in the commands (possibility of errors)
– slow having to type in commands every time
Any one advantage of GUI from:
– only need to click on one simple picture
– so much easier for the novice
– several instructions are replaced by one icon
– no need to understand how computer systems work
Any one disadvantage of GUI from:
– wasteful of computer memory
– if user wants to communicate with computer system directly, GUI is effectively
more complex.
(b) Any three from:
– handling interrupts
– input/output/peripheral/device control
– spooling
– multitasking/JCL/batch processing
– multiprogramming
– user interface
– load/run software
– processor management/task management
– file (copy/save/delete etc) management
– memory management
– user accounts
– utility tasks (defrag, format etc.)
– error handling
– security management
– power management
[3]
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Mark Scheme: Teacher version
GCE O LEVEL – May/June 2011
Syllabus
7010
Paper
12
(a) Any two from:
– access to undesirable websites
– increased risk of hacking
– greater volume of junk mail
– theft of computer time by staff (using the internet instead of working e.g.
downloading games)
– increased risk of viruses and other security issues
[2]
(b) Any two from:
– can set up specific information pages
– can limit places where the intranet can be accessed
– better security since network is internal/LAN
– faster to find information since it is restricted to company info only
No Internet based answers.
[2]
5
Application
Virtual reality
application
Disabled person
communicating
with a computer
system
Automatic stock
control system
at a
supermarket
Input Device
Reason for choice of device
–
–
data gloves
data goggles
–
allows user to interact with v/r
system directly
–
sensor suits
–
system needs to get data
directly from its surroundings
–
microphone
–
–
head wand
–
–
large keyboard
–
allows blind person to dictate
text directly to the computer
if little hand movement, allows
user to select options from the
screen
people with poor eye sight can
use the keyboard to input text
–
–
bar code reader
RFID tag reader
–
–
automatically reads data
fewer data entry errors
–
touch screen
–
–
easier for the customers
reduces the number of possible
options for the user
select options from a screen
immovable/more secure
Information
kiosk at an
airport using a
GUI interface
–
–
–
trackerball
May see other devices .e.g. Kimball tag reader
NOT mouse, NOT keyboard
[8]
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Mark Scheme: Teacher version
GCE O LEVEL – May/June 2011
Syllabus
7010
Paper
12
1 mark per correct link
Data loss caused by hard
disk head crash
Anti-virus software
Hacking into files and
changing or deleting data
Encryption
Introduction of software
that self-replicates and can
cause data loss
Anti–spyware software
Reading of illegally
accessed documents
Make back-up files
Software that logs/records
all key presses on your
computer without you
knowing
Use of passwords and a
firewall
[5]
(a) 1 mark for each error identified + suggested correction
line 5:
this should read if x > h then h = x
line 7:
print h should come after the end of the repeat loop
line 8:
this should read until c = 20 or until c >= 20 or until c > 19
[3]
(b) Any two from:
– close to English
– one statement is equal to many low-level language statements
– portable
– easy to edit/debug/update
– problem oriented
– needs converting to machine code before execution
[2]
(c) Any one from:
– interpreter – runs line by line and locates errors as it runs
– compiler – converts whole program into object code/gives complete list of errors
[1]
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Mark Scheme: Teacher version
GCE O LEVEL – May/June 2011
Page 6
8
Syllabus
7010
Paper
12
(a) (i) drop down menu/list / combobox
(ii) Any one from:
– can limit number of choices
– allows only specific answers to be given
– fast way of choosing options
– reduces chances of any errors
[2]
(b) (i) Any one from:
– length check
– character/type check
– presence check
– format check
NOT range check.
[1]
(ii) 1 mark for each type of test data + 1 mark for an example:
Normal data:
– input ID with 9 characters e.g. 123456789 or abc456789
Erroneous/abnormal data:
– input number with digits missing e.g. 123 789
Example must match (i)
9
[4]
(a) Any one from:
– takes up much less memory space/smaller file size
– faster download time
– MP3 track 1/10th the size of a CD track
[1]
(b) 1 mark for showing relevant working + 1 mark for correct answer
40 tracks = 40 x 3.5 = 1 40 Mbyte
56 megabits/sec = 7 Mbyte/sec
time to download tracks = 140/7
i.e. 20 seconds
[2]
(c) 1 mark for showing relevant working + 1 mark for correct answer
36 photos = 36 x 1.8 = 64.8 Mbyte
16 megabits/sec = 2 Mbyte/sec
time to upload photos = 64.8/2
i.e. 32.4 secs
[2]
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Mark Scheme: Teacher version
GCE O LEVEL – May/June 2011
Page 7
Syllabus
7010
Paper
12
10 (a)
N
sum
x
count
0
0
0
1
5
1
2
5
16
2
3
11
32
3
4
16
1
28
4
5
–4
2
18
5
6
–10
26
6
7
8
36
7
8
10
33
8
9
–3
50
9
10
17
60
10
11
10
3
T
average
6
1 mark
1 mark
1 mark
1 mark
1 mark
1 mark
(b) 6, 3
[6]
[1]
11 (a) (i)
A
0
0
1
1
B
0
1
0
1
C
0
1
1
1
}
}
1 mark
1 mark
[2]
(ii) OR gate
[1]
(b) (i)
A
0
0
1
1
B
0
1
0
1
C
0
0
0
1
}
}
1 mark
1 mark
[2]
(ii) AND gate
[1]
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Mark Scheme: Teacher version
GCE O LEVEL – May/June 2011
Page 8
Syllabus
7010
Paper
12
12 (a) Any three from:
– sensors detect magnets
– send signals to the computer
– signals changed to digital using ADC
– computer checks all previous positions ...
– ... which are stored in memory/on file
– and determines which piece has moved
[3]
(b) Any two from:
– legal/acceptable moves stored in memory/on file
– computer can calculate which squares the piece is allowed to move to
– computer tracks each move made by each piece
– compare actual move with permissible move
[2]
(c) –
[1]
expert system/Artificial Intelligence
13 Any three advantages from:
– can shop 24–7/in own time
– worldwide therefore greater choice
– no need to waste money on travelling to shops
– no need to waste time travelling
– disabled/elderly people don’t have to leave their homes
– cost savings often passed on to customer
– can look for “best value” in a short time
– less pollution since fewer car journeys
Any two disadvantages from:
– shops close down in cities/unemployment/”ghost towns”
– increased risk of fraud/hacking
– less social interaction between people
– can’t see the goods first
– goods may not arrive/”bogus” web sites
– environmental issues/wasted packaging
– “ties up” the phone line if broadband not available
– increase in phone bills
[5]
14 (a) 1 mark for correct formula in D2 and 1 mark for correct replication
1
2
3
4
5
6
7
8
D
scale length (m)
= B2/C2
= B3/C3
= B4/C4
= B5/C5
= B6/C6
= B7/C7
[2]
[1]
(b) (i) Y
(ii) = IF (D7 > 0.25, “Y”, “N”)
[1]
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Mark Scheme: Teacher version
GCE O LEVEL – May/June 2011
Syllabus
7010
Paper
12
(c) Any two from:
– select cell (e.g. C1)
– select DATA and choose FILTER (autofilter)
– choose 18 on drop down box
– only rows where 18th scale models will show
– draw bar chart using column C
– colour bars differently where scale = 18
– conditional formatting
– colour cells differently where scale = 18
[2]
15 1 mark for each storage method + appropriate example
– magnetic
– e.g. floppy disk, hard disk, magnetic tape
–
optical
– e.g. CD, DVD, Blu-ray etc
–
solid state
– e.g. flash memory
[3]
16 (a) (i) Barcode
(ii) Any two from:
– a book is republished
– new copies of book arrive
– new books published (new titles)
– errors in one of the fields
– book is sold/removed from stock
[3]
(b) (i) Any one from:
– computer re-calculates check digit
– compares it to check digit in data sent
(ii) Any one from:
– missing digit (e.g. 3156 instead of 31516)
– transposed digit (e.g. 35116 instead of 31516)
– erroneous digit (e.g. 33516 instead of 31516)
[2]
(c) Book title:
– character/type check
– presence check
Copies:
– range check
– character/type check
– length check
– presence check
Publication date:
– range check
– format check
– presence check
All checks must be different.
[3]
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Mark Scheme: Teacher version
GCE O LEVEL – May/June 2011
17 (a) marking points
Initialisation
loop control
input student id
input start and leaving dates
check if leaving date <(=) starting date// check if
starting date >(=) leaving date
increment error total
output error total
Syllabus
7010
Paper
12
1 mark
1 mark
1 mark
1 mark
1 mark
1 mark
1 mark
sample algorithm
total = 0
for x = 1 to 1800
input student id
input start date, leaving date
if leaving date <= start date then total = total + 1
next x
print total
(1)
Initialisation must be for the error counter. Inputs must be inside the loop, output must
be outside the loop.
[5]
(1)
(1)
(1)
(1)
(2)
(b) normal data that will be accepted:
– e.g. 110906 and 220710 or 060911 and 100722
abnormal data that should be rejected:
– e.g. 150911 and 201009 or 110915 and 091020
negative numbers that should be rejected:
– e.g. –110209 or –090211
month/day/year out of range that should be rejected:
– e.g. 352210 or 102235
use of text that should be rejected:
– e.g. September 15, 2010 or 15th September 2010
Marks are for examples and a brief description. Must have both description and
example for each mark.
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UNIVERSITY OF CAMBRIDGE INTERNATIONAL EXAMINATIONS
General Certificate of Education Ordinary Level
*9601420634*
7010/11
COMPUTER STUDIES
October/November 2011
Paper 1
2 hours 30 minutes
Candidates answer on the Question Paper.
No Additional Materials are required.
READ THESE INSTRUCTIONS FIRST
Write your Centre number, candidate number and name on all the work you hand in.
Write in dark blue or black pen.
You may use a soft pencil for any diagrams, graphs or rough working.
Do not use staples, paper clips, highlighters, glue or correction fluid.
DO NOT WRITE IN ANY BARCODES.
Answer all questions.
No marks will be awarded for using brand names of software packages or hardware.
At the end of the examination, fasten all your work securely together.
The number of marks is given in brackets [ ] at the end of each question or part question.
For Examiner's Use
This document consists of 19 printed pages and 1 blank page.
IB11 11_7010_11/FP
© UCLES 2011
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2
(a) Give one benefit of storing music files in MP3 format.
[1]
(b) Describe the type of memory used in MP3 players.
[2]
3
Give three features expected in a data protection act.
1
2
3
[3]
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4
The following flowchart shows how barcodes are used at the point of sale in an automatic
stock control system.
For
Examiner's
Use
Select statements from the list below, using numbers only, to complete the flowchart.
START
READ barcode
on item
No
Yes
No.
1
2
3
4
5
6
7
8
9
Yes
No
Yes
No
STOP
List of statements
any more barcodes to read?
find barcode in stock database
has item already been ordered?
has barcode been found in file?
has barcode scanned correctly?
is number in stock <= reorder level?
manually key in barcode
send out orders to suppliers
subtract 1 from item stock level
Yes
No
Yes
No
[5]
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5
(a) State what is meant by Computer Aided Design (CAD).
For
Examiner's
Use
[1]
(b) Give three different applications that make use of CAD.
1
2
3
[3]
(c) Name three specialist input/output devices used in CAD.
1
2
3
[3]
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6
(a) Name two pieces of hardware needed to enable video-conferencing to take place
using a standard computer system.
For
Examiner's
Use
1
2
[2]
(b) State one piece of specialist software needed to carry out video-conferencing.
[1]
(c) A company has decided to use video-conferencing rather than instant messaging.
(i) Give one advantage of doing this.
(ii) Give one disadvantage of doing this.
[2]
(d) Give one reason why use of video-conferencing has increased over the last ten years.
[1]
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7
Carefully study the following flowchart:
For
Examiner's
Use
START
INPUT
number
count = 1: total = 0: neg = 0
INPUT
temp
Yes
temp >= 20 ?
total = total + temp
No
Yes
temp <= 0 ?
neg = neg + 1
No
count = count + 1
Yes
count <= number ?
No
OUTPUT
total, neg
STOP
Complete the trace tables for the following two sets of test data:
(i) number = 7, temp = -5, 0, 5, -4, 0, 10, -2
(ii) number = 6, temp = 21, 20, 30, 19, 21, 15
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(i) trace table:
number
count
temp
total
neg
OUTPUT
count
temp
total
neg
OUTPUT
For
Examiner's
Use
(ii) trace table:
number
[6]
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8
You have been asked to write an article on how an expert system is developed.
What would you include in your article?
For
Examiner's
Use
[3]
9
A spreadsheet has been designed to calculate the fuel economy for 6 cars:
1
2
3
4
5
6
7
8
9
A
car
car 1
car 2
car 3
car 4
car 5
car 6
B
distance (km)
48
160
70
200
150
300
C
fuel used (litres)
4.0
9.0
4.5
20.0
33.0
15.0
average economy:
best economy:
D
economy (km/litre)
12.0
17.8
15.6
10.0
4.5
20.0
13.3
20.0
(a) (i) What formula is in cell D2 to calculate the economy for car 1?
(ii) What formula is in cell D8 to calculate the average economy for all 6 cars?
(iii) What formula is in cell D9 to calculate the best (highest) economy?
[3]
(b) If cell B7 was changed to 200, which cells would be automatically updated?
[2]
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(c) Fuel economy is often given in the form litres per 100 km. A column E is to be added
to the spreadsheet to contain these new economy values.
For
Examiner's
Use
What formula needs to be in E7 to find the economy of car 6 in litres per 100 km?
[2]
10 A company’s technical services are now available on the Internet as well as using call
centres.
(a) Give two advantages to the customer of using call centres.
1
2
[2]
(b) Give two advantages to the customer of using technical services on the Internet.
1
2
[2]
(c) Describe two effects on company staff of replacing the call centres with Internet
services.
1
2
[2]
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0
11 Computer memories are measured in terms of the number of bytes.
For
Examiner's
Use
(a) (i) What is meant by the term byte?
(ii) What is meant by a Gigabyte?
[2]
(b) Flash memories and CD-RWs are used as backing media for computers.
Give two differences between these two media.
1
2
[2]
12 The conditions in a fish tank are being controlled using sensors and a microprocessor. To
keep the fish healthy, the temperature must be at 25°C and the oxygen content needs to be
20 ppm (parts per million). The tank contains a heater and an oxygen inlet controlled by a
valve.
heater
oxygen supply
sensor A
sensor B
microprocessor
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(a) Name the two sensors used in this application.
For
Examiner's
Use
Sensor A
Sensor B
[2]
(b) Describe how the sensors and the microprocessor are used to maintain the correct
conditions in the fish tank.
[4]
(c) What safeguards would be needed to stop the fish tank temperature rising too high?
[1]
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2
13 Aeroplanes now use Global Positioning Systems (GPS) to determine their location.
For
Examiner's
Use
(a) Describe how the computer on board the aeroplane uses GPS to find its exact location.
[4]
(b) Give two benefits of using GPS in this application.
1
2
[2]
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4
14 An alarm, X, gives a signal (i.e. X = 1) when a car fuel injection system gives certain fault
conditions. The inputs are:
input
P
R
T
binary value
0
1
0
1
0
1
condition
pressure < 5 bar
pressure >= 5 bar
revs > 8000 rpm
revs <= 8000 rpm
temp > 120 °C
temp <= 120 °C
The alarm returns a value of 1 if:
either
(i) pressure < 5 bar AND revs > 8000 rpm
or
(ii) revs <= 8000 rpm AND temp > 120 °C
(a) Draw the logic circuit for the above system using these logic gates.
NOT
AND
OR
[6]
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5
(b) Complete the truth table for this alarm system.
P
R
T
0
0
0
0
0
1
0
1
0
0
1
1
1
0
0
1
0
1
1
1
0
1
1
1
For
Examiner's
Use
X
[4]
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6
15 A company selling CDs uses a unique 6-digit identification number for each CD title. The
right-most digit (position 1) is a check digit.
For example,
digit position
identification number
6 5 4 3 2 1
3 0 6 1 4 9
check digit
The validity of the number and check digit is calculated as follows:
•
•
•
•
multiply each digit by its digit position
add up the results of the multiplications
divide the answer by 11
if the remainder is 0, the identification number and check digit are valid
(a) Show whether the following identification numbers are valid or not. You must show
how you arrived at your answer.
(i) 4 2 1 9 2 3
working:
valid or not valid?
(ii) 8 2 0 1 5 6
working:
valid or not valid?
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7
(b) Find the check digit for the following identification number:
5 0 2 4 1
For
Examiner's
Use
working:
check digit:
[2]
(c) Describe, with examples, two different types of data entry errors that a check digit
would detect.
1
2
[2]
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8
16 A company has bought some computers which can be used as stand-alone or networked.
(a) When used as stand-alone, there is a risk of information being stolen.
Give two ways this risk could be removed or minimised.
1
2
[2]
(b) There are additional, different security risks when using the computers on a network.
Describe two of these risks and how the system can be protected against them.
Risk 1
Protection
Risk 2
Protection
[4]
(c) The company use a star network which is linked externally to the Internet.
(i) Draw a labelled diagram of a star network.
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9
(ii) Another type of network is a ring. Give one advantage of a star network when
compared to a ring network.
For
Examiner's
Use
[2]
(d) The company also decides to buy some laptop computers for use on the network.
Give two desirable properties you would look for in the laptop processors.
1
2
[2]
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0
17 (a) Write an algorithm, using pseudocode or flowchart only, which:
•
•
For
Examiner's
Use
inputs three numbers
outputs the largest of the three numbers
[3]
(b) Write an algorithm, using pseudocode or flowchart only, which:
•
•
inputs 1000 numbers
outputs how many of these numbers were whole numbers (integers)
(You may use INT(X) in your answer e.g. Y = INT(3.8) gives the value Y = 3)
[4]
Permission to reproduce items where third party owned material protected by copyright is included has been sought and cleared where possible. Every
reasonable effort has been made by the publisher (UCLES) to trace copyright holders, but if any items requiring clearance have unwittingly been included, the
publisher will be pleased to make amends at the earliest possible opportunity.
University of Cambridge International Examinations is part of the Cambridge Assessment Group. Cambridge Assessment is the brand name of University of
Cambridge Local Examinations Syndicate (UCLES), which is itself a department of the University of Cambridge.
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UNIVERSITY OF CAMBRIDGE INTERNATIONAL EXAMINATIONS
GCE Ordinary Level
MARK SCHEME for the October/November 2011 question paper
for the guidance of teachers
7010 COMPUTER STUDIES
7010/11
Paper 1, maximum raw mark 100
This mark scheme is published as an aid to teachers and candidates, to indicate the requirements of
the examination. It shows the basis on which Examiners were instructed to award marks. It does not
indicate the details of the discussions that took place at an Examiners’ meeting before marking began,
which would have considered the acceptability of alternative answers.
Mark schemes must be read in conjunction with the question papers and the report on the
examination.
• Cambridge will not enter into discussions or correspondence in connection with these mark schemes.
Cambridge is publishing the mark schemes for the October/November 2011 question papers for most
IGCSE, GCE Advanced Level and Advanced Subsidiary Level syllabuses and some Ordinary Level
syllabuses.
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Mark Scheme: Teacher version
GCE O LEVEL – October/November 2011
Syllabus
7010
Paper
11
Any three from:
– fact finding
– feasibility study
– analysis
– design
– testing
– documentation
– implementation/changeover/installation
– evaluation
– maintenance
[3]
(a) Any one from:
– file size is small
– fast to download/upload files
– format can be played on several types of devices, e.g. mobile phone, CD player, laptop
etc.
[1]
(b) Any two from:
– type of EEPROM
– non-volatile memories
– solid state memories
– NAND based memories
– mini hard disk drives
3
[2]
Any three from:
– data must be up to date
– data can only be read/used for the purpose for which it was collected
– data must be accurate/relevant
– data must be deleted/destroyed when no longer needed/don’t keep longer than necessary
– data must be secure
– data user must register what data is held
– data must be used /collected fairly and lawfully
– data must be protected from accidental damage
– only authorised people can have access to the data
– fines will be imposed for data mis-use
– data should not be passed on to 3rd parties without owner’s permission
– person can view data and have it changed if necessary
[3]
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Mark Scheme: Teacher version
GCE O LEVEL – October/November 2011
Syllabus
7010
Paper
11
4
START
READ bar code on
next item
1 mark
No
5
Yes
7
2
1 mark
Yes
1 mark
1
No
4
No
Yes
STOP
Yes
6
1 mark
No
No
3
8
Yes
1 mark
9
[5]
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Mark Scheme: Teacher version
GCE O LEVEL – October/November 2011
Syllabus
7010
Paper
11
(a) Any one from:
– software that can be used to design new products/amend existing products
– makes use of features such as 2D, 3D, wire frames, library of parts, links to CAM
[1]
(b) Any three from:
– aerospace
– architecture
– designing cars
– designing consumer goods
– chemical/nuclear plant design
– designing electronic circuit boards
– ergonomic design
– landscape/garden design
[3]
(c) Any three from:
– large monitor/screen with hi-res
– touch screen
– plotter
– space mouse/space ball/4D device
– 3D glasses (in some applications)
– light pen
– graphics tablet
– 3D printer
– 3D scanner
[3]
(a) Any two from:
– webcam
– speakers
– microphone
– broadband modem
[2]
(b) Any one from:
– use of CODEC (converts/compresses analogue data into digital data)
– echo cancellation s/ware (allows talking in real time/keeps everything in sync)
– compression s/ware for video/audio
– s/ware to access broadband/networking
[1]
(c) (i) Any one from:
– immediate response to questions/queries
– can see each other watch body language etc.
– easier to have several participants (would be difficult using instant messaging if
several people involved)
– would take a long time typing out each question
(ii) Any one from:
– need for expensive equipment/high set up costs
– sometimes synchronisation problems make it difficult for delegates
– need to train people to use the new technology
– greater use of bandwidth
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Mark Scheme: Teacher version
GCE O LEVEL – October/November 2011
Page 5
Syllabus
7010
Paper
11
(d) Any one from:
– faster communications now widely available
– safety reasons, e.g. increase in terrorist attacks on international flights
– reduced transportation/accommodation/hardware costs
– environmental issues, e.g. reduced carbon footprint
– increase in multinational working
7
[1]
(i)
number
count
temp
total
neg
0
0
OUTPUT
7
1
2
–5
1
3
0
2
4
5
5
–4
3
6
0
4
7
10
8
–2
5
0, 5
< - - - - - 1 mark - - - - - - >< - - - - - 1 mark - - - - - ->< - - - - - 1 mark - - - - - ->
(ii)
number
count
temp
total
neg
0
0
OUTPUT
6
1
2
21
21
3
20
41
4
30
71
5
19
6
21
7
15
92
92, 0
< - - - - - 1 mark - - - - - - >< - - - - - 1 mark - - - - - ->< - - - - - 1 mark - - - - - ->
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Mark Scheme: Teacher version
GCE O LEVEL – October/November 2011
Syllabus
7010
Paper
11
Any three from:
– gather information from experts
– design the knowledge base
– create/enter data into the knowledge base
– design/create the inference engine
– design/create the rules base
– develop the input interface/interrogation technique
– test system fully with known outcomes
– create structure to relate each item in the knowledge base
– design method of displaying results
– expert system shell
[3]
(a) (i) = B2/C2
[1]
(ii) = AVERAGE(D2:D7) OR
= SUM(D2:D7)/6 OR
= (D2 + D3 + D4 + D5 + D6 + D7)/6
[1]
(iii) = MAX(D2:D7)
[1]
(b) D7, D8, D9
[2]
(c) = (C7/B7) * 100
[2]
10 (a) Any two from:
– available to those who don’t have an Internet connection
– many people prefer the human contact
– often better talking to a human/can develop query
– faster response to a question once connected
– easier to resolve more complex problems (can take user through steps to solution to
problem)
[2]
(b) Any two from:
– no need to wait in a queue
– no problem with language/dialect/accent/culture differences
– open 24-7/can leave question on website any time
– customer can save/print solution for later referral
– multimedia services available (e.g. ‘How to’ videos)
[2]
(c) Any two from:
– job losses
– de-skilling
– need to (re-)train
– more jobs for technical staff
– possible job sharing/flexi-hours/working from home
[2]
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Mark Scheme: Teacher version
GCE O LEVEL – October/November 2011
Syllabus
7010
Paper
11
11 (a) (i) Any one from:
– unit of data/memory
– 8 bits
– used to represent a character
[1]
(ii) Any one from:
– 230 bytes
– 1 073 741 824 bytes
– 1 048 576 kilobytes
– 1024 megabytes
[1]
(b) Any two from:
Flash memory
– magnetic media/solid state memory
– no formatting issues
– plugs directly into the USB port
– direct transfer of data
CD-RW
– optical media
– slower access speed/flash memory has faster access speed
– requires a separate drive
– data needs to be burnt/finalised/finished (before being used on another device)
12 (a) Only answers:
– temperature (sensor)
– oxygen (sensor)
[2]
[2]
(b) Any four from:
– information from the sensors sent to microprocessor
– the ADC converts the analogue data into digital form
– if temperature < 25ºC OR temperature checked against stored value
– ...microprocessor sends signal to heater/actuator/valve...
– ...to switch on heater
– if oxygen level < 20 ppm OR oxygen level checked against stored value
– ...to open valve/oxygen supply
– use of DAC between microprocessor and devices
– sounds an alarm if system unable to respond
– continuously monitors sensor inputs
– any reference to feedback
[4]
(c) Any one from:
– unsafe limit stored in memory
– warning sound/signal if too high a value reached
– fail safe switch off in case of a malfunction
[1]
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Mark Scheme: Teacher version
GCE O LEVEL – October/November 2011
Syllabus
7010
Paper
11
13 (a) Any four from:
– satellites transmit signals to onboard computers
– computers receive/interpret these signals
– system depends on very accurate timing/use of atomic clocks
– each satellite transmits data indicating location and time
– computer in aeroplane calculates location based on at least three satellites
– at least 24 satellites in operation at any one time
– position accurate to within one metre
– can also calculate altitude of aeroplane
– ref to “triangulation”:
satellite 1
exact
location
of
aeroplane
satellite 2
satellite 3
[4]
(b) Any two from:
– safer as known location is exact/more accurate
– reduces possibility of pilot error
– allows accurate estimation of arrival time
– display and guide pilot to nearest airport in case of emergency
[2]
14 (a) 1 mark for each correct logic gate:
NOT
P
AND
R
NOT
OR
X
AND
T
NOT
[6]
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Mark Scheme: Teacher version
GCE O LEVEL – October/November 2011
Page 9
Syllabus
7010
Paper
11
(b)
P
R
T
X
0
0
0
1
0
0
1
1
0
1
0
1
0
1
1
0
1
0
0
0
1
0
1
0
1
1
0
1
1
1
1
0
]
1 mk
]
1 mk
]
1 mk
]
1 mk
[4]
15 (a) 1 mark for the correct working in BOTH parts
1 mark for valid
1 mark for not valid
(i) working
= (4 × 6) + (2 × 5) + (1 × 4) + (9 × 3) + (2 × 2) + (3 × 1)
= 24 + 10 + 4 + 27 + 4 + 3
= 72 ÷ 11
= 6 remainder 6
valid/not valid: NOT valid
(ii) working
= (8 × 6) + (2 × 5) + (0 × 4) + (1 × 3) + (5 × 2) + (6 × 1)
= 48 + 10 + 0 + 3 + 10 + 6
= 77 ÷ 11
= 7 remainder 0
valid/not valid: VALID
[3]
(b) 1 mark for correct working + 1 mark for check digit
working
= (5 × 6) + (0 × 5) + (2 × 4) + (4 × 3) + (1 × 2)
= 30 + 0 + 8 + 12 + 2
= 52
need to add 3 to make the total 55 (i.e. exactly divisible by 11)
check digit: 3
[2]
(c) 2 digits transposed
(e.g. 280419 becomes 280149/ two digits have been switched)
incorrect digit
(e.g. 280419 becomes 250419/ one of the digits has been mistyped)
[2]
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Mark Scheme: Teacher version
GCE O LEVEL – October/November 2011
Syllabus
7010
Paper
11
16 (a) Any two from:
– lock the room/computer
– use/prevent use of removable storage media
– passwords and/or ids (to get into the system)
– log off when computer not attended
– encrypt data
[2]
(b) 1 mark for each risk + 1 mark for associated protection method.
risk:
protection:
virus
use ant-virus software
risk:
protection:
hacking
passwords/ids
firewalls
risk:
protection:
use of wifi systems
passwords/ids
firewalls
risk:
protection:
phishing:
don’t open websites from “unknown” emails
anti-phishing software
risk:
protection:
pharming:
check certification of website under properties
check spelling of websites
use a well respected ISP
[4]
(c) (i)
[1]
(ii) Any one from:
– if one station/cable fails, others are not affected
– easier to identify faults when using star topologies
– it is easier to expand this type of network
– performance doesn’t deteriorate under load
[1]
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Mark Scheme: Teacher version
GCE O LEVEL – October/November 2011
Syllabus
7010
Paper
11
(d) Any two from:
– processor should consume as little power as possible (thus prolonging the battery life)
– processor should run as cool as possible (minimising problems associated with heat
dissipation)
– no fans needed to cool processor (thus reducing the load on the internal battery)
[2]
17 (a) marking points:
the way to find and print the largest value a
the way to find and print the largest value b
the way to find and print the largest value c
sample algorithm:
input a, b, c
if a > b and a > c then print a
else if b > c then print b
else print c
1 mark
1 mark
1 mark
(1 mark)
(1 mark)
(1 mark)
(b) marking points:
loop construct
check if number is an integer
counting the number of integers input
output count value (outside the loop)
sample algorithm:
for x = 1 to 1000
input number
difference = INT(number) – number
if difference = 0 then total = total + 1
next x
print total
(NOTE: alternative to lines 3 and 4:
if INT(number) = number then total = total + 1
[3]
1 mark
1 mark
1 mark
1 mark
(1 mark)
(1 mark)
(1 mark)
(1 mark)
(2 marks) )
[4]
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UNIVERSITY OF CAMBRIDGE INTERNATIONAL EXAMINATIONS
General Certificate of Education Ordinary Level
*7462525026*
7010/13
COMPUTER STUDIES
October/November 2011
Paper 1
2 hours 30 minutes
Candidates answer on the Question Paper.
No Additional Materials are required.
READ THESE INSTRUCTIONS FIRST
Write your Centre number, candidate number and name on all the work you hand in.
Write in dark blue or black pen.
You may use a soft pencil for any diagrams, graphs or rough working.
Do not use staples, paper clips, highlighters, glue or correction fluid.
DO NOT WRITE IN ANY BARCODES.
Answer all questions.
No marks will be awarded for using brand names of software packages or hardware.
At the end of the examination, fasten all your work securely together.
The number of marks is given in brackets [ ] at the end of each question or part question.
For Examiner's Use
This document consists of 20 printed pages.
IB11 11_7010_13/FP
© UCLES 2011
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1
(a) Give two benefits of networking a set of computers.
For
Examiner's
Use
1
2
[2]
(b) A college decides to use network computers with wireless capability.
Give one advantage and one disadvantage of using wireless systems.
Advantage:
Disadvantage:
[2]
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2
The following table shows three applications which require specialist output devices.
For each application, suggest one possible output device and give a reason for your
choice.
Application
Output device
For
Examiner's
Use
Reason for choice of device
A visually impaired
person using a word
processor
Using CAD to design
a new engine
Monitoring a house
for burglars
[6]
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3
A user wishes to use a word processing application. They can either use a command line
interface (CLI) or a graphical user interface (GUI) to open this application.
(a) Describe how both methods could be used to select the application including any input
hardware needed.
(i) CLI
(ii) GUI
[4]
(b) (i) What is meant by automatic data capture?
(ii) Name a device used in automatic data capture and describe an application that
uses it.
Device:
Application:
[3]
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4
Five definitions and descriptions are shown below on the left hand side.
For
Examiner's
Use
Five computer terms are shown on the right.
Match the definitions/descriptions on the left to the correct term on the right by drawing
connecting arrows.
check if students’ ages are
in the range 11 to 18
verification
computer generated
operation of a chemical
process
validation
software that looks for
information based on certain
key words
simulation
system where all the data
are collected first before
being processed in one go
search engine
typing in a password twice
to ensure it is correct
batch processing
[5]
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6
(a) What is meant by the term web browser?
For
Examiner's
Use
[1]
(b) Rock-ICT has set up a website as shown below:
ROCK – ICT
Home
(i)
Sales
Basket
Checkout
Payment
(ii)
credit card
Choose your payment method:
debit card
click here to go to CD website
(iii)
Give the names of the three parts that have been labelled:
(i)
(ii)
(iii)
[3]
(c) How does the website recognise the user’s buying preferences as soon as they visit
the website?
[1]
(d) Hacking is one security issue associated with the Internet and emails.
State two other security issues.
1
2
[2]
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7
The following flowchart inputs the size of a number of car engines; a value of -1 stops the
input.
The following information is output: average engine size and number of engines with size
> 1.5.
START
engine = 0: count = 0: number = 0
INPUT
size
is size
= –1 ?
Yes
average = engine/number
OUTPUT
average, count
No
is size
> 1.5 ?
Yes
STOP
count = count + 1
No
number = number + 1
engine = engine + size
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290
Complete the trace table for the following input data:
1.8, 2.0, 1.0, 1.3, 1.0, 2.5, 2.0, 1.3, 1.8, 1.3,
engine
count
number
size
For
Examiner's
Use
-1
average
OUTPUT
[6]
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0
8
Robots are being introduced into a factory which makes engines.
For
Examiner's
Use
(a) Describe three ways this could affect the workers.
1
2
3
[3]
(b) One of the many advantages to management is the reduction in overall costs.
Give two reasons why using robots could reduce costs.
1
2
[2]
(c) Give two other advantages to the management of introducing robots.
1
2
[2]
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9
A spreadsheet was set up to compare passenger costs for five airlines.
A
1
2
3
4
5
6
7
Flight id
AA 151
AT 304
BR 106
CD 221
EX 115
B
Distance
(km)
3 000
2 000
1 500
8 000
6 000
C
Number of
passengers
240
320
150
400
280
D
Total revenue
($)
60 000
80 000
45 000
360 000
140 000
Average cost:
For
Examiner's
Use
E
Cost per
passenger ($)
250
250
300
900
500
(a) What formula must be in E2 to calculate the cost per passenger.
[1]
(b) Cell E7 is to contain the average passenger cost.
What formula would need to be placed in this cell?
[1]
(c) It was decided to add two new columns (F and G) to find out if the airline made a profit
or loss on each flight. The costs per flight are calculated by multiplying Distance (km)
by 1/10th of the Number of passengers.
(i) What formulas must be in column F?
F
1
Flight costs ($)
2
3
4
5
6
[2]
(ii) The formula = IF (F2 > D2, “Loss”, “Profit”) was added to cell G2. What would
be output?
[1]
(iii) What formula would be in G5 after replication down from G2?
[1]
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2
10 A computer system is being used to monitor and control a chemical process.
For
Examiner's
Use
gases out
temperature sensor
chemical
process
computer
heater
pressure sensor
valve
gases in
(a) Data are collected from sensors at regular intervals and compared with stored values.
(i) Describe how the computer uses this data when monitoring the chemical
process.
[1]
(ii) Describe how the computer uses this data when controlling the chemical process.
[1]
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3
(b) What steps are necessary for the computer to control the temperature of the chemical
process?
For
Examiner's
Use
[3]
(c) Name two other sensors and give a different application where they are used.
sensor 1:
application:
sensor 2:
application:
[4]
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4
11 A digital alarm clock is controlled by a microprocessor. It uses the 24-hour clock system
(i.e. 6 pm is 18:00).
Each digit in a typical display is represented by a 4-digit binary code:
For example:
8
4
2
1
0
0
0
0
1st digit (0)
1
0
0
0
2nd digit (8)
0
0
1
1
3rd digit (3)
0
1
0
1
4th digit (5)
is represented by:
(clock display)
(a) What time is shown on the clock display if the 4-digit binary codes are:
8
4
2
1
0
0
0
1
0
1
1
0
0
1
0
0
1
0
0
1
(clock display)
[2]
(b) What would be stored in the 4-digit binary codes if the clock display time was:
8
4
2
1
1st digit
2nd digit
3rd digit
4th digit
[4]
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.
296
5
(c) The clock alarm has been set at 08:00.
Describe the actions of the microprocessor which enable the alarm to sound at 08:00.
For
Examiner's
Use
[2]
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6
12 A database has been set up to show details about countries. Part of the database is shown
below.
Country
code
CH
IN
PO
BO
TI
BR
RO
SA
ZA
Country
China
India
Poland
Bolivia
Tibet
Brazil
Romania
Saudi Arabia
Zambia
Area
Population
(millions
(millions)
sq km)
9.6
1320
3.8
1150
0.3
39
1.1
9
1.2
2
8.5
192
0.2
22
2.2
28
0.7
12
Continent
Asia
Asia
Europe
America
Asia
America
Europe
Asia
Africa
Coastline
Yes
Yes
Yes
No
No
Yes
No
Yes
No
Currency
yuan
rupee
zloty
boliviano
yuan
real
leu
riyal
kwacha
(a) How many fields are in each record?
[1]
(b) Using Country code only, what would be output if the following search condition was
used?
(Population (millions) > 1000) OR (Continent = “Asia”)
[2]
(c) Write down a search condition to find which countries have a land area less than 3
million square km and also have a coastline.
[2]
(d) If the database was sorted in descending order of population size, using
Country code only, what would be the order of countries in the database?
[2]
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7
13 The following flowchart shows how barcodes are used when a customer buys items from
the supermarket. Barcodes are used to find the prices and to carry out stock control.
Several stages are missing from the flowchart. These stages are shown in the item list
below.
For
Examiner's
Use
Insert the correct statements, using numbers only, to complete the flowchart.
START
scan in the next barcode
has
barcode been
found?
has
barcode been
found?
No
Yes
Yes
Yes
No
No
No
Yes
Yes
No
No.
1
2
3
4
5
6
7
8
9
10
11
List of statements
any more items to scan?
decrease stock level by 1
key in barcode number manually
print “error”
print out the order form
print out the itemised bill
get price and display item price
scan in coupons, loyalty cards, etc
has stock already been ordered?
is stock <= minimum stock level?
customer makes payment
STOP
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8
14 An alarm, Y, sends a signal (Y = 1) when certain fault conditions in a chemical process are
detected. The inputs are:
Input
A
T
S
Binary value
1
0
1
0
1
0
Condition
acidity > 5
acidity <= 5
temperature >= 120UC
temperature < 120UC
stirrer bar ON
stirrer bar OFF
The alarm, Y, returns a value of 1 if:
either
(i) temperature >= 120UC AND stirrer bar is OFF
or
(ii) acidity > 5 AND temperature < 120UC
(a) Draw the logic circuit for the above system using these logic gates.
NOT
AND
OR
[5]
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9
(b) Complete the truth table for this alarm system.
A
T
S
0
0
0
0
0
1
0
1
0
0
1
1
1
0
0
1
0
1
1
1
0
1
1
1
For
Examiner's
Use
Y
[4]
15 A student gave the following three computer definitions.
Give the name of the term being described in each case.
(i) “a signal from a device sent to a computer causing the CPU to stop its current
operation temporarily”
(ii) “an exchange of signals between two devices when communicating to ensure
synchronisation”
(iii) “a temporary memory to store data waiting to be sent to a device”
[3]
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0
16 The weather conditions in a town are being monitored over a year (365 days). The values
recorded per day are weather type and temperature (e.g. CLOUDY, 25).
For
Examiner's
Use
Write an algorithm, using pseudocode or flowchart only, which:
•
•
•
•
inputs the weather type and temperature for each day
outputs the number of days that were CLOUDY, RAINING, SUNNY or FOGGY
outputs the highest recorded temperature for the year
outputs the lowest recorded temperature for the year
[6]
Permission to reproduce items where third party owned material protected by copyright is included has been sought and cleared where possible. Every
reasonable effort has been made by the publisher (UCLES) to trace copyright holders, but if any items requiring clearance have unwittingly been included, the
publisher will be pleased to make amends at the earliest possible opportunity.
University of Cambridge International Examinations is part of the Cambridge Assessment Group. Cambridge Assessment is the brand name of University of
Cambridge Local Examinations Syndicate (UCLES), which is itself a department of the University of Cambridge.
© UCLES 2011
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UNIVERSITY OF CAMBRIDGE INTERNATIONAL EXAMINATIONS
GCE Ordinary Level
MARK SCHEME for the October/November 2011 question paper
for the guidance of teachers
7010 COMPUTER STUDIES
7010/13
Paper 1, maximum raw mark 100
This mark scheme is published as an aid to teachers and candidates, to indicate the requirements of
the examination. It shows the basis on which Examiners were instructed to award marks. It does not
indicate the details of the discussions that took place at an Examiners’ meeting before marking began,
which would have considered the acceptability of alternative answers.
Mark schemes must be read in conjunction with the question papers and the report on the
examination.
• Cambridge will not enter into discussions or correspondence in connection with these mark schemes.
Cambridge is publishing the mark schemes for the October/November 2011 question papers for most
IGCSE, GCE Advanced Level and Advanced Subsidiary Level syllabuses and some Ordinary Level
syllabuses.
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Mark Scheme: Teacher version
GCE O LEVEL – October/November 2011
Syllabus
7010
Paper
13
(a) Any two from:
– share resources (hardware and software)
– easier communications are possible
– possible to work from any work station and access files/data
– central data source
– easier to control/monitor what users are doing
– easier to ‘globally’ protect against unauthorised access
[2]
(b) Any one advantage and any one disadvantage from:
Advantages
– no trailing wires (therefore safer, less expensive since no cables)
– allows users to work anywhere (portability)
– can set up network in places where cable runs are not possible (e.g. outside, historic
buildings etc.)
Disadvantages
– limited range
– certain items (like filing cabinets) can block the signals
– possible to ‘tap’ into WiFi if it isn’t secure
– often slower data transfer rate than a wired system
– needs additional hardware
– number of access points need to match computers
2
[2]
1 mark per point (max of 2 marks per application)
Application
Output device
Reason for choice of device
A disabled
person using a
word processor
– speakers
– Braille printers
– allows blind people to hear output
from word processors
– blind people can read printed output
Using CAD to
design a new
engine
– plotter
– large monitor
– 3D printer
– accurate print out of large drawings
– allows easy editing of drawings
– produce working prototypes in resin
Monitoring a
house for
burglars
– buzzer
– light
– alarm
– to warn of intruder’s presence in the
building
[6]
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Mark Scheme: Teacher version
GCE O LEVEL – October/November 2011
Page 3
3
Syllabus
7010
Paper
13
(a) 1 mark for each description + 1 mark for each example of h/ware
CLI description
– user communicates by typing in commands (in response to a prompt)
– several commands are entered to carry out a task (such as loading software)
CLI h/ware
– keyboard
– keypad
GUI description
– user interacts with a computer using pictures and symbols (icons)/drop-down menu
– tasks are initiated by selecting the icon
– usually part of a windows/wimp environment
GUI h/ware
– pointing device (e.g. mouse)
– touch screen
(b) (i) –
[4]
saving/collecting data with no actual need for human interaction
(ii) 1 mark for named device + 1 mark for matching application: if device is wrong then no
application mark
Device
– barcode reader
– document scanner
–
–
mag stripe reader
microphone
–
OCR/OMR/MICR
–
–
–
–
–
RFID
retina scan/finger prints
video camera
correct sensor
data logger
Application
used in automatic stock control
transferring printed documents into an electronic form for
storage on computer
electronic funds transfer/entry through ‘locks’
part of voice recognition – automatically picking up
sounds in burglar detection
transferring documents to computer, reading multiple
choice answers in a survey, reading cheques
tracking animals/people/items/vehicles
security systems
security surveillance
control applications
used to monitor a parameter in an experiment
[3]
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Mark Scheme: Teacher version
GCE O LEVEL – October/November 2011
Syllabus
7010
Paper
13
1 mark per correct match
check if student’s ages are in the
range 11 to 18
verification
computer generated operation of a
chemical process
validation
software that looks for information
based on certain key words
simulation
system where all the data is first
collected before being processed in
one go
Typing in a password twice to
ensure it is correct
search engine
batch processing
[5]
5
(a) user documentation:
– helps users learn how to use/operate the software
technical documentation
– designed to help programmers to make improvements to the system
– helps programmers to repair/maintain the system
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Mark Scheme: Teacher version
GCE O LEVEL – October/November 2011
Syllabus
7010
Paper
13
(b) 1 mark for 3 correct answers, 2 marks for 4 to 6 correct answers and 3 marks if all 7 answers
correct.
Item
how to save a file
User
documentation
only
Technical
documentation
only
Both user and
technical
documentation
√
program listing/coding
√
hardware and software
requirements
√
file structures
√
list of variables
√
how to load the software
√
meaning of errors/error
messages
√
[3]
6
(a) –
program/software that allows a user to display web pages, web sites, etc.
NOT access the Internet
[1]
(b) (i) webpage (part of)
(ii) radio button
(iii) hyperlink NOT link
[3]
(c) reference to cookies or description of cookie
[1]
(d) Any two from:
– phishing
– pharming
– viruses
– key logging or malware
– spyware
Rationale: fishing and farming not acceptable
[2]
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Mark Scheme: Teacher version
GCE O LEVEL – October/November 2011
Syllabus
7010
Paper
13
7
engine
count
number
size
0
0
0
1.8
1.8
1
1
2.0
3.8
2
2
1.0
4.8
3
1.3
6.1
4
1.0
5
2.5
6
2.0
7.1
3
9.6
11.6
4
7
1.3
12.9
5
8
1.8
14.7
9
1.3
16.0
10
(–1)
average
OUTPUT
1.6
(1mk)
8
(1 mk)
(1 mk)
(1 mk)
(1 mk)
1.6, 5
(1 mk)
[6]
(a) Any three from:
– unemployment
– need to re-train
– cleaner/less noisy environment
– safer environment
– possible de-skilling
– less heavy lifting
– reskilling with description
– redeployment (could lead to new employment e.g. maintaining robots)
[3]
(b) Any two from:
– less lighting/heating/air con costs since few people now in factory
– no need to pay wages/salary
– greater productivity (therefore lower unit cost)
– can work non-stop/24-7 (no breaks/holiday)
[2]
(c) Any two from:
– more consistent product
– can work non-stop (no breaks, holidays, etc.)/24-7
– don’t go on strike
– can be used in a dangerous environment
– greater productivity
[2]
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Mark Scheme: Teacher version
GCE O LEVEL – October/November 2011
Page 7
9
Syllabus
7010
Paper
13
(a) = D2/C2
[1]
(b) = AVERAGE(E2:E6) OR
= SUM(E2:E6)/5 OR
= (E2 + E3 + E4 + E5 + E6)/5
[1]
(c) (i) 1 mark for formula in F2 and 1 mark for all other formulas correct
F
1
Flight costs ($)
2
= B2 * C2/10
3
= B3 * C3/10
4
= B4 * C4/10
5
= B5 * C5/10
6
= B6 * C6/10
[2]
(ii) Loss
[1]
(iii) = IF (F5 > D5, “Loss”, “Profit”)
[1]
10 (a) Any two from:
(i) monitoring
– decide if the temperature/pressure are out of range
– give a warning if out of range/doesn’t change the process parameters
[1]
(ii) control
– send signal to open/close valve, switch on/off a heater etc.
– output affects the input
[1]
(b) Any three from:
– data from temperature/pressure sensor…
– …changed into digital by ADC
– data is sent to computer
– data/input is compared to values in memory
– if temperature too low, signal sent to heater…
– if pressure too low, signal sent to valve…
– and heater turned on/valve opened
– use of DAC
– use of actuators
– monitoring/control system continues to loop indefinitely
[3]
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Mark Scheme: Teacher version
GCE O LEVEL – October/November 2011
Page 8
Syllabus
7010
Paper
13
(c) 1 mark for each sensor + 1 mark for each related application
sensor
– light
–
sound
–
infra red
–
moisture
–
–
–
–
–
gas
pH
smoke
motion sensor/accelerometer
proximity
application
greenhouse environment
open/close automatic doors
burglar alarm
listening for sounds in pipes etc.
burglar alarm
detecting people (e.g. entering a building)
greenhouse environment
check if clothes dry in a drier
detection of gas leaks
soil acidity in greenhouse
in buildings for fire detection
vibrations in machinery
parking cars
[4]
11 (a) 1 6 : 4 9
1 mk
1 mk
(b) 0
0
0
1
0
1
0
0
0
1
1
0
1
1
0
1
[2]
1st digit
2nd digit
3rd digit
4th digit
[4]
(c) Any two from:
– microprocessor compares present time with stored time
– if the values are the same
– sends signal to sound alarm
[2]
12 (a) 7
[1]
(b) CH, IN, TI, SA
[2]
(c) (Area (millions sq km) < 3) AND (Coastline = “Yes”)
< - - - - - - - 1 mark - - - - - - ->< - - - - - - 1 mark - - - - - - >
OR
(Coastline = “Yes”) AND (Area (millions sq km) < 3)
< - - - 1 mark - - - - >< - - - - - - - - 1 mark - - - - - - - - - >
[2]
(d) CH, IN, BR, PO, SA, RO, ZA, BO, TI
[2]
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Mark Scheme: Teacher version
GCE O LEVEL – October/November 2011
Page 9
Syllabus
7010
Paper
13
13
START
scan in the next barcode
No
has bar
code been
found?
No
Has bar
code been
found?
3
Yes
Yes
4
7/2
(1 mark)
(1 mark)
2/7
Yes
10
Yes
Yes
No
(1 mark)
No
9
5
(1 mark)
1
No
8/11
11/8
6
(1 mark)
[5]
STOP
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Mark Scheme: Teacher version
GCE O LEVEL – October/November 2011
Syllabus
7010
Paper
13
14 (a) 1 mark for each logic gate:
A
AND
NOT
Y
OR
T
S
AND
NOT
[5]
(b)
A
T
S
Y
0
0
0
0
0
0
1
0
0
1
0
1
0
1
1
0
1
0
0
1
1
0
1
1
1
1
0
1
1
1
1
0
}
]
]
]
]
1 mk
1 mk
1 mk
1 mk
[4]
15
(i) interrupt
(ii) handshaking
(iii) buffer
[3]
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Mark Scheme: Teacher version
GCE O LEVEL – October/November 2011
16 Marking points
initialise variables
correct loop control
input (in correct place)
correct check on type of weather (if, case, etc.)
adding number of days of each type of weather
check for the highest temperature
check for the lowest temperature
output (all items in the correct place)
Sample algorithm
c = 0: r = 0: s = 0: f = 0
high = 0 (or a negative number)
low = 1000
for x = 1 to 365
input weather, temp
if weather = “CLOUDY” then c = c + 1
else if weather = “RAINING” then r = r + 1
else if weather = “SUNNY” then s = s + 1
else if weather = “FOGGY” then f = f + 1
endif
if temp > high then high = temp
if temp < low then low = temp
next x
print c, r, s, f, high, low
Syllabus
7010
Paper
13
1 mark
1 mark
1 mark
1 mark
1 mark
1 mark
1 mark
1 mark
(1 mark)
(1 mark)
(1 mark)
(2 marks)
(1 mark)
(1 mark)
(1 mark)
[6]
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UNIVERSITY OF CAMBRIDGE INTERNATIONAL EXAMINATIONS
General Certificate of Education Ordinary Level
*9661836479*
7010/11
COMPUTER STUDIES
Paper 1
May/June 2012
2 hours 30 minutes
Candidates answer on the Question Paper.
No Additional Materials are required.
READ THESE INSTRUCTIONS FIRST
Write your Centre number, candidate number and name on all the work you hand in.
Write in dark blue or black pen.
You may use a soft pencil for any diagrams, graphs or rough working.
Do not use staples, paper clips, highlighters, glue or correction fluid.
DO NOT WRITE IN ANY BARCODES.
Answer all questions.
No marks will be awarded for using brand names of software packages or hardware.
At the end of the examination, fasten all your work securely together.
The number of marks is given in brackets [ ] at the end of each question or part question.
For Examiner's Use
This document consists of 21 printed pages and 3 blank pages.
IB12 06_7010_11/FP
© UCLES 2012
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1
Video conferencing, Voice over Internet Protocol (VoIP) and instant messaging are all used
as communication methods. Certain devices are essential to enable each of these
communication methods to be used.
Tick () the appropriate cells in the table below to show which one or more devices are
essential for each method.
keyboard
microphone
speaker
webcam
VoIP
video
conferencing
instant
messaging
[3]
2
Describe ways to guard against each of the following Internet security issues. (A different
method should be given in each case.)
viruses
hacking
spyware
phishing
tapping into wireless networks
[5]
© UCLES 2012
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Examiner's
Use
.
315
3
An airport is converting all its manual information systems to computerised systems.
For
Examiner's
Use
(a) One stage in analysing the existing system is fact finding.
State three methods of fact finding:
1
2
3
[3]
(b) Which of your named methods would be best suited to this application?
Give two reasons for your choice.
Method
Reason 1
Reason 2
[2]
4
Michael is preparing a multimedia presentation.
(a) What three features should he include in his presentation to make it more interesting?
1
2
3
[3]
(b) Give two reasons why a presentation would be better than just printing out and
distributing a newsletter.
1
2
[2]
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5
A floor turtle can use the following instructions.
Instruction
For
Examiner's
Use
Meaning
FORWARD x
Move x cm forwards
LEFT t
Turn left t degrees
RIGHT t
Turn right t degrees
REPEAT n
Repeat next set of instructions n times
ENDREPEAT
Finish repeated instructions
PENUP
Lift the pen
PENDOWN
Lower the pen
Each square =
10 cm by 10 cm
45°
Each diagonal
line = 14 cm
45°
Start
© UCLES 2012
Finish
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Complete the set of instructions to draw the above shape in the direction shown by the
arrows.
For
Examiner's
Use
PENDOWN
FORWARD 20
LEFT 90
[5]
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6
Carefully study the following flowchart.
For
Examiner's
Use
START
C=1
L=0
N=0
S=0
T=0
INPUT A, B
Is A > B ?
Yes
L=L+1
N=A–B
S=S+1
N=B–A
No
Is B > A ?
Yes
No
N=0
T=T+N
C=C+1
Is C < = 10 ?
No
Yes
OUTPUT L, S, T
STOP
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(a) Complete the trace table for the following data:
8, 4,
3, 1,
C
5, 8,
L
4, 2,
N
1, 3,
2, 2,
S
1, 2,
T
5, 5,
A
4, 0,
For
Examiner's
Use
5, 4
B
[6]
(b) What is the final output from the algorithm?
L=
S=
T=
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[2]
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7
A large hotel has a website. The website offers the following facilities:
•
•
•
For
Examiner's
Use
a virtual tour of the hotel
an interactive map
the ability to book rooms online
(a) Give two features you would expect to find in each facility.
virtual tour
1
2
interactive map
1
2
room booking online
1
2
[6]
(b) Describe one other feature you would expect to see on the hotel’s website.
[1]
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8
A spreadsheet has been set up to record employees’ hotel expenses for one year.
The data for one employee is shown below.
A
1
2
3
4
5
6
7
Hotel
Grand
Station
Northern
Western
George
Quality
B
Tariff
Sunday to
Thursday
($)
150
200
90
120
180
100
C
Tariff
Friday to
Saturday
($)
90
120
60
80
100
70
D
No of
nights
(Sunday to
Thursday)
3
2
5
4
2
3
E
No of
nights
(Friday to
Saturday)
2
1
0
1
2
1
For
Examiner's
Use
F
G
Total
cost ($)
630
520
450
560
560
370
Maximum
allowance
($)
600
800
360
480
720
400
(a) What formula is in F2 to calculate the employee’s costs at the Grand Hotel?
[2]
(b) The maximum allowance is four times the Sunday to Thursday tariff.
What formula is in G2?
[1]
(c) A manager wants to know whether an employee exceeded their maximum allowance at
each hotel.
Describe how the spreadsheet could be used to do this.
[2]
(d) A macro was written to convert the tariff rate into different currencies. The exchange
rate was taken directly from a website.
What is the advantage of using a macro to do this?
[1]
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0
9
Vehicles passing over a bridge are detected automatically using sensors and a computer.
For
Examiner's
Use
(a) What sensors could be used?
[1]
(b) The graph below shows the number of vehicles counted during certain periods of the day.
This graph is produced automatically at the end of each day.
Number of vehicles
Bridge traffic on
1 March 2012
80
70
60
50
40
30
20
10
0
12-6
6-9
9-12
12-4
4-12
Time period
A record is created each time a vehicle is detected. These records are processed to
generate the graph and for other purposes.
What data need to be stored in each record?
[2]
(c) State two other methods of automatic data capture. In each case, name an application
which would use this method.
Method 1
Application 1
Method 2
Application 2
[4]
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10 Jatinder uses Internet banking.
For
Examiner's
Use
(a) Give one benefit and one drawback of using Internet banking.
Benefit
Drawback
[2]
She uses a 5-digit PIN.
(b) Every time she logs on, she is asked to give 3 random digits from the PIN. She was
asked to give her 3rd, 1st and 4th digit. This changes every time she logs on.
Give a reason for this.
[1]
(c) A different application needs the whole PIN to be input.
The following code has been written to check the PIN:
c = 0
INPUT PIN
x = PIN
REPEAT
x = x/10
c = c + 1
UNTIL x < 1
IF c < 5
THEN
PRINT “error in PIN entered”
ELSE
PRINT “PIN OK”
ENDIF
(i) What value of c and what message would be output if the following PINs were
entered?
5 1 0 2 0 Value of c:
Message:
5120
Value of c:
Message:
[2]
(ii) What type of validation check is being carried out here?
[1]
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2
11 A simulation using a mathematical model is being used to forecast the weather one week in
advance.
(a) (i) State what data are gathered for this model.
(ii) Explain how the data are gathered for this model.
[2]
(b) (i) Describe how the simulation can predict the weather for the next seven days.
(ii) Describe in what format the predicted weather can be shown.
[2]
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Use
.
325
4
12 (a) (i) Complete the truth table for the following logic circuit, which is made up of NAND
gates:
A
X
B
A
B
0
0
0
1
1
0
1
1
X
[2]
(ii) What single logic gate has the same function as the above logic circuit?
[1]
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Examiner's
Use
.
326
5
(b) Complete the truth table for the following logic circuit:
A
For
Examiner's
Use
AND
B
OR
X
OR
C
NOT
A
B
C
0
0
0
0
0
1
0
1
0
0
1
1
1
0
0
1
0
1
1
1
0
1
1
1
X
[4]
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6
13 Andrew is sending a large document to a printer.
(a) State the name for the area of memory used to store temporarily the data being sent to
the printer.
[1]
(b) The printer runs out of paper during the printing job. A signal is sent back to the
computer to temporarily stop its current task.
Name this type of signal.
[1]
(c) When trying to save this document after it was printed, the computer stops responding.
Give two reasons why the computer might stop responding.
1
2
[2]
(d) Andrew ended up losing his electronic document.
How could that have been prevented?
[1]
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Examiner's
Use
.
328
7
14 A database was set up to show the properties of certain chemical elements. Part of the
database is shown below.
Name of
element
Element
Symbol
oxygen
iron
mercury
bromine
osmium
caesium
gallium
argon
silver
O
Fe
Hg
Br
Os
Cs
Ga
Ar
Ag
Atomic
Number
Atomic
Weight
8
26
80
35
76
55
31
18
47
Melting
Boiling
Point (C) Point (C)
16
56
201
80
190
133
70
40
108
- 218
1538
- 38
-7
3033
28
30
- 189
961
- 183
2861
356
59
5012
671
2204
- 186
2162
For
Examiner's
Use
State at
room temp
gas
solid
liquid
liquid
solid
solid
solid
gas
solid
(a) How many fields are in each record?
[1]
(b) The following search condition was entered:
(Melting Point (C) < 40) AND (Atomic Weight > 100)
Using Element Symbol only, which records would be output?
[2]
(c) We need to know which elements have an atomic number greater than 50 and are
solid at room temperature.
Write down the search condition to find out these elements.
[2]
(d) The data are to be sorted in descending order of Boiling Point (C).
Write down the new order of records using the Element Symbol only.
[2]
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8
15 A vending machine has the choices shown below.
10
tea
11
with milk
12
with sugar
20
coffee
21
with milk
22
with sugar
30
hot chocolate
31
extra milk
32
extra sugar
40
cold water
41
hot water
42
fizzy water
50
coke
51
orange
52
lemon
60
chicken soup
61
tomato soup
with milk and
sugar
with milk and
23
sugar
with extra milk
33
and extra sugar
13
A customer uses a keypad to make their choice. Each number entered is represented in a
6-bit binary register.
For example, key press 33 (hot chocolate with extra milk and extra sugar) is represented
by:
1
0
0
0
0
1
32
16
8
4
2
1
(a) (i) If a customer chooses coffee with milk and sugar what is the key press?
(ii) How is it represented in the 6-bit register?
32
16
8
4
2
1
[2]
(b) If the 6-bit register shows
1
0
1
0
0
1
what drink has the customer chosen?
[1]
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Examiner's
Use
.
330
9
(c) A customer using the vending machine gets an error message after keying in their
selection.
For
Examiner's
Use
What could have caused this error message?
[1]
(d) It was decided to split the register so that each digit was represented by its own 3-bit
register:
For example,
4 2 would now be represented as:
1
0
0
0
1
0
4
2
1
4
2
1
(i) What drink has been chosen if the 3-bit registers contain:
1
1
0
0
0
0
4
2
1
4
2
1
[1]
(ii) How would the lemon option be shown on both types of register?
4
32
2
16
1
4
8
4
2
2
1
1
[2]
(iii) What is the advantage of using two 3-bit registers rather than one 6-bit register?
[1]
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0
16 A car park uses sensors and a microprocessor to monitor cars leaving and entering.
The car park is open 24 hours every day. The parking fee is $10 per day.
The following flowchart shows how the IN and OUT barriers are controlled. Some of the
statements are missing.
Using item numbers only, insert the correct item numbers into the flowchart from the item
list.
START
read the IN
sensor
any signal
received from
IN sensor?
No
read the OUT
sensor
Yes
No
Yes
Yes
No
No
Yes
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For
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Use
.
332
List of statements
Item Number
For
Examiner's
Use
Description
1
activate motor to raise IN barrier
2
activate motor to raise OUT barrier
3
any signal received from OUT sensor?
4
decrease number of cars in car park by 1
5
increase number of cars in car park by 1
6
is car park full?
7
is the car park fee paid?
8
OUTPUT “car park full”
9
OUTPUT “please pay car park fee at pay machine”
10
use ADC to convert IN sensor signal to digital
11
use ADC to convert OUT sensor signal to digital
12
use DAC to convert computer signal to analogue signal to operate IN barrier
13
use DAC to convert computer signal to analogue signal to operate OUT barrier
14
wait 30 seconds and then close barrier
[6]
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2
17 Write an algorithm, using pseudocode or a program flowchart only, which:
•
•
•
•
For
Examiner's
Use
inputs the population and land area for 500 countries,
calculates the population density (i.e. population/land area) for every country,
outputs the largest and smallest population density,
outputs the average population for all 500 countries.
[6]
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UNIVERSITY OF CAMBRIDGE INTERNATIONAL EXAMINATIONS
GCE Ordinary Level
MARK SCHEME for the May/June 2012 question paper
for the guidance of teachers
7010 COMPUTER STUDIES
7010/11
Paper 1, maximum raw mark 100
This mark scheme is published as an aid to teachers and candidates, to indicate the requirements of
the examination. It shows the basis on which Examiners were instructed to award marks. It does not
indicate the details of the discussions that took place at an Examiners’ meeting before marking began,
which would have considered the acceptability of alternative answers.
Mark schemes must be read in conjunction with the question papers and the report on the
examination.
• Cambridge will not enter into discussions or correspondence in connection with these mark schemes.
Cambridge is publishing the mark schemes for the May/June 2012 question papers for most IGCSE,
GCE Advanced Level and Advanced Subsidiary Level syllabuses and some Ordinary Level
syllabuses.
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Mark Scheme: Teacher version
GCE O LEVEL – May/June 2012
Page 2
1
Syllabus
7010
Paper
11
1 mark per correct row.
keyboard
microphone
speaker
VoIP
video
conferencing
instant
messaging
webcam
Correct Answer Only
2
[3]
viruses e.g.
– use anti-virus software // regular virus scans
– don’t open/use disks // don’t open email attachments from unknown sources
Hacking e.g.
– passwords / user IDs
– firewalls
Spyware e.g.
– anti-spyware software
– delete cookies at end of session
Phishing e.g.
– don’t open emails from unknown sources
– don’t divulge personal information via email / unsecure website
– ensure that the site viewed has a valid security certificate (SSL)
3
tapping into wireless networks e.g.
– secured wifi network (protected by passwords)
– encryption / WEP
– no broadcast of network ID
[5]
(a) Any three from:
– questionnaires
– interviews
– observation
– looking at existing paperwork
[3]
(b) 0 marks for name, 2 marks for reasons which MUST tie up with name
Questionnaires / interviews
– possible to obtain information direct from customers
– possible to obtain information direct from staff
– customers/staff can take questionnaires away to answer in own time
– interviews allow first hand information to be gathered/questions -asked can be tailored to
the individual
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Mark Scheme: Teacher version
GCE O LEVEL – May/June 2012
Page 3
Syllabus
7010
Paper
11
Observation / existing paperwork
– sees first hand airport operations
– doesn’t rely on opinions of customers/staff
– helps determine what hardware is needed
– helps to determine memory size/storage devices
4
5
[2]
(a) Any three from:
– sound
– animations
– video
– links to Internet websites
– slide transitions
– use of colours
[3]
(b) Any two from:
– less expensive because e.g. no paper/ink required
– can be interactive (chance to ask questions)
– can explain things better because e.g. addition of animation/video
– newsletters tend to be thrown away without reading/need distributing
[2]
pendown
forward 20
left 90
-----------forward 10
right 90
forward 20
-----------right 90
forward 40
right 90
forward 20
right 90
-----------forward 10
right 45
forward 14
-----------repeat 3
left 90
forward 14
endrepeat
-----------right 135
forward 20
(PENUP)
(1 mark)
(1 mark)
(1 mark)
or
or
or
or
left 90
forward 14
left 90
forward 14
left 90
forward 14
(1 mark)
(1 mark)
[5]
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Mark Scheme: Teacher version
GCE O LEVEL – May/June 2012
Page 4
6
Syllabus
7010
Paper
11
(a)
C
L
N
S
T
A
B
1
0
0
0
0
8
4
2
1
4
4
3
1
3
2
2
6
5
8
9
4
2
11
1
3
13
2
2
13
1
2
14
5
5
4
5
3
3
1
2
6
2
2
7
0
8
1
9
0
14
4
0
5
4
3
10
4
4
18
11
5
1
19
1 mark
1 mark
1 mark
1 mark
1 mark
< - - - - 1 mark - - - - >
[6]
(b) L = 5
}
}
S=3 }
T = 19 }
1 mark
1 mark
[2]
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Mark Scheme: Teacher version
GCE O LEVEL – May/June 2012
Syllabus
7010
Paper
11
(a) virtual tour
Any two from:
– hot spots to move from room to room
– ability to zoom in and out of rooms
– ability to rotate around the room (panning)
– voiceovers
interactive map
Any two from:
– how to get to hotel from some starting point on the map
– use of satellite photos and map superimposed
– zoom in/zoom out
– move north, south, east and west
– use of “pin head” to show location of hotel
– hotspots with information on that area
– how to get from one part of the hotel to another
room booking online
Any two from:
– calendar function// room availability for given dates
– type of room
– number of guests
– price per room
– hotel facilities e.g. breakfast/full board/half board
– special requirements
– special offers
– payment
8
[6]
(b) Any one from:
– safe credit card payment facility
– hyperlinks to other web pages/websites
– local weather forecast
[1]
(a) = (D2 * B2) + (E2 * C2)
1 mark
1 mark
[2]
(b) = B2 * 4
[1]
© University of Cambridge International Examinations 2012
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Mark Scheme: Teacher version
GCE O LEVEL – May/June 2012
Page 6
Syllabus
7010
Paper
11
(c) Any two from:
– use (=) IF(F2 > G2, “exceeded”, “within range”)
– replicate formula down to row 7
OR
– F2-G2
– if result is positive …
OR
– draw graph of data in columns F and G
– compare values on graph to determine if exceeded
OR
– drawing line of unit gradient (on a scatter graph of total cost versus maximum allowance)
– compare values on graph to determine if exceeded
[2]
9
(d) Any one from:
– automatic calculation
– no need to create formula (etc.) every time on the spreadsheet
– can be assigned to a keyboard shortcut and launched
[1]
(a) Any one from:
– infra red sensor
– pressure sensor/induction loop
– radar
[1]
(b) –
–
[2]
time of day
date
(c) 1 mark for name + 1 mark for correct application
– barcode e.g. – stock taking in supermarket
– getting prices at POS
– library system
– tracking systems (e.g. parcels)
– RFID e.g. – identifying/tracking individual items (livestock, vehicles, people)
– biometrics e.g. – finger printing, face images, etc. as security systems
– magnetic stripe e.g. – security cards (e.g. hotel room keys)
– credit/debit cards/ATMs/banking
– loyalty cards
– OCR/OMR e.g. – scanning in documents/photos/exam papers
– microphones e.g. – interface (input) to a computer (used by disabled people)
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Mark Scheme: Teacher version
GCE O LEVEL – May/June 2012
Page 7
Syllabus
7010
Paper
11
10 (a) Any one benefit and one drawback from:
benefit:
– can bank at any time 24/7
– save money on travelling
– save time not travelling to bank
– can bank from anywhere
– can do transactions/look after account
drawbacks:
– need computer equipment/internet
– fear of hacking , viruses, etc.
– lack of one to one with bank
– creation of “ghost towns”
– reduced socialising
– cause of redundancies
– possibility of mismanaging account
– lack of counter services (drawing out cash)
[2]
(b) Any one from:
– stops hackers getting all of the PIN characters
[1]
(c) (i) 51020:
5120:
value of c:
message:
5
PIN OK
(1 mark)
value of c:
message:
4
ERROR
(1 mark)
[2]
(ii) length check
[1]
11 (a) (i) what data is gathered:
Any one from:
–
pressure
–
temperature
–
humidity
–
wind speed/direction
–
historic data
[1]
(ii) how data is gathered:
Any one from:
– sensors
– satellites
– airline pilots send in information
– meteorological/weather balloons/station
[1]
(b) (i) Any one from:
– information from sensors/satellites sent to computer
– data compared to stored information
– which contains known weather patterns
– predictions made based on these comparisons
– expert system
[1]
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Mark Scheme: Teacher version
GCE O LEVEL – May/June 2012
Page 8
Syllabus
7010
Paper
11
(ii) Any one from:
– produces weather maps showing isobars, etc.
– computer can show weather changes graphically/by animations
[1]
12 (a) (i)
A
B
X
0
0
0
0
1
1
1
0
1
1
1
1
}
}
1 mark
1 mark
[2]
(ii) OR gate
[1]
(b)
A
B
C
X
0
0
0
1
0
0
1
0
0
1
0
1
0
1
1
1
1
0
0
1
1
0
1
0
1
1
0
1
1
1
1
1
}
}
}
}
1 mark
1 mark
1 mark
1 mark
[4]
13 (a) Any one from:
– buffer
– RAM
(b) –
[1]
interrupt
[1]
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GCE O LEVEL – May/June 2012
Page 9
Syllabus
7010
Paper
11
(c) Any two from:
– hardware problem (e.g. head crash on disk drive)
– software “glitch”
– viruses
– disconnected printer cable
– automatic update in progress
– too many applications open
[2]
(d) Any one from:
– backup the document
– enable automatic saving of work
– manually save document every 10 minutes
– save before printing
[1]
14 (a) 7
[1]
(b) Hg, Cs
(1) (1) Correct Answer Only
(c) (Atomic Number > 50)
[2]
AND
(State at room temp = “solid”)
< - - - - - 1 mark - - - - -> < - - - - - - - - - - - 1 mark - - - - - - - - - - ->
Or
(State at room temp = “solid”)
AND
(Atomic Number > 50)
< - - - - - - -1 mark - - - - - - - >
< - - - - - - - - -1 mark - - - - - - - - >
Must use exact spelling
[2]
(d) Os, Fe, Ga, Ag, Cs, Hg, Br, O, Ar
[2]
15 (a) key press:
2
3
represented by:
0
1
0
1
1
1
[2]
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GCE O LEVEL – May/June 2012
Page 10
(b) drink chosen:
Syllabus
7010
Paper
11
hot water/41
[1]
(c) Any one from:
– incorrect number typed/keyed in
– not one of the accepted codes used
– code not recognised
– machine malfunction (e.g. no cups)
[1]
(d) (i) –
[1]
chicken soup/60
(ii)
5
2
1
0
1
1
1
0
1
0
1
0
0
0
[2]
(iii) –
–
gives an additional row of options
now have 0 to 77 instead of only 0 to 63
[1]
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Mark Scheme: Teacher version
GCE O LEVEL – May/June 2012
Page 11
Syllabus
7010
Paper
11
16
START
read the IN
sensor
No
any signal
received from
IN sensor?
read the OUT
sensor
Yes
10
No
3
1 mark
Yes
Yes
6
8
1 mark
11
No
4”
5*
1 mark
12*
No
7
1 mark
9
Yes
13”
1*
1 mark
2”
1 mark
14
[6]
*Instead of 5, 12, 1 can have:
12, 1, 5
12, 5, 1
“instead of 4, , 13, 2 can have:
13, , 2, 4
13, , 4, 2
© University of Cambridge International Examinations 2012
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Mark Scheme: Teacher version
GCE O LEVEL – May/June 2012
Syllabus
7010
Paper
11
17 marking points
•
•
•
•
•
•
•
•
Initialisation (smallest, largest, total) (could be first input)
correct loop (also: repeat .... until n = 500, while n <> 500 do ....)
input (inside a loop)
calculate the density
check on largest density + action taken
check on smallest density + action taken
find population total + calculate average population
print values (outside loop + some evidence of processing taking place)
e.g.
smallest = 10000: largest = 0: total = 0
for country = 1 to 500
input population, area
density = population/area
if density > largest then largest = density
if density < smallest then smallest = density
total = total + population
next country
average = total/500
print largest, smallest, average
(1 mark)
(1 mark)
(1 mark)
(1 mark)
(1 mark)
(1 mark)
(1 mark)
(1 mark)
[6]
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UNIVERSITY OF CAMBRIDGE INTERNATIONAL EXAMINATIONS
General Certificate of Education Ordinary Level
*7791387147*
7010/12
COMPUTER STUDIES
May/June 2012
Paper 1
2 hours 30 minutes
Candidates answer on the Question Paper.
No Additional Materials are required.
READ THESE INSTRUCTIONS FIRST
Write your Centre number, candidate number and name on all the work you hand in.
Write in dark blue or black pen.
You may use a soft pencil for any diagrams, graphs or rough working.
Do not use staples, paper clips, highlighters, glue or correction fluid.
DO NOT WRITE IN ANY BARCODES.
Answer all questions.
No marks will be awarded for using brand names of software packages or hardware.
At the end of the examination, fasten all your work securely together.
The number of marks is given in brackets [ ] at the end of each question or part question.
For Examiner's Use
This document consists of 20 printed pages.
IB12 06_7010_12/FP
© UCLES 2012
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2
Both email and mobile phones can be used to send messages.
Give one advantage and one disadvantage of using each method when compared to each
other.
(i) Email:
Advantage
Disadvantage
(ii) Mobile phones:
Advantage
Disadvantage
[4]
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3
A computer system is to have wireless access (Wi-Fi) to the Internet.
For
Examiner's
Use
State five potential security issues.
1
2
3
4
5
[5]
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4
A list of four printers and four different applications which use printers is shown below.
For
Examiner's
Use
(a) Using arrows, link each printer to the most appropriate application.
Printing documents in a
factory environment which
is dusty and damp
3D printer
High quality printing of
30 000 colour booklets per
day
Dot matrix printer
Producing prototypes in
resin of a new design
Colour inkjet printer
Producing a colour poster
Colour laser printer
[4]
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(b) Give one feature of each printer which makes it appropriate for the application.
For
Examiner's
Use
3D printer
Dot matrix printer
Colour inkjet printer
Colour laser printer
[4]
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5
(a) Give three features you would expect to see in a typical Computer Aided Design (CAD)
program.
1
2
3
[3]
(b) Describe three specialist output devices which could be used with a CAD program
when developing a new product.
1
2
3
[3]
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352
(c) Describe two potential health risks and one potential safety risk when using computer
systems.
For
Examiner's
Use
Health risk 1
Health risk 2
Safety risk
[3]
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6
Carefully study the following flowchart:
For
Examiner's
Use
START
M = 32
T=1
S=0
C=1
INPUT D
T=D*M
M = M/2
S=S+T
C=C+1
Yes
No
OUTPUT S
STOP
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(a) Complete the trace table for the following data:
For
Examiner's
Use
1, 0, 1, 1, 0, 1
M
T
S
C
D
[4]
(b) What process does this flowchart perform?
[1]
(c) Predict the output from the flowchart for an input of 1, 1, 1, 1, 0, 0
[1]
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0
7
An expert system is being developed to diagnose faults in electronic equipment. Each piece
of equipment is made up of the following components:
•
•
•
•
•
screen
keypad (containing F1 to F9 keys)
sound card and speakers
RAM and ROM
microphone
(a) The following series of questions were asked by the expert system. The responses by
the user are also shown:
Response
Question
Is the screen operating?
Yes
If the F2 key is pressed, does the screen go green?
Yes
If the F1 key is pressed, can sound output be heard?
No
(i) In which component is the fault likely to be?
[1]
(ii) What would the expert system do next to help diagnose the exact fault in the
component(s)?
[2]
(iii) What output would the expert system produce?
[1]
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.
356
(b) An expert system has an input-output interface. State three other parts that make up a
typical expert system.
For
Examiner's
Use
1
2
3
[3]
(c) The electronic equipment contains RAM and ROM.
Give one use of each type of memory.
RAM
ROM
[2]
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2
8
Body mass index (bmi) is calculated using the following formula:
bmi =
For
Examiner's
Use
weight
(height)2
Six people’s data are shown in the spreadsheet below:
A
1
name
2
3
4
5
6
7
8
Theo
Sujatmi
Angela
Juan
Jatinder
Igor
B
C
weight
(kg)
70.0
63.6
72.4
110.0
76.4
70.5
height
(m)
1.87
2.03
1.70
1.90
1.65
1.98
D
bmi
E
underweight,
normal or
overweight
F
20.0
15.4
25.1
30.5
28.1
18.0
(a) What formulas must be in column D to calculate each person’s bmi?
D
1
bmi
2
3
4
5
6
7
[2]
(b) Column E indicates whether the person is underweight, normal or overweight.
(i) The following formula was typed into E2:
= IF(D2<18.5, “underweight”, IF(D2>25, “overweight”, “normal”))
What output would appear in E2?
[1]
(ii) What formula needs to be placed in D8 to find the average (mean) bmi?
[1]
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3
(iii) If the formula in E2 were replicated down to E8, what formula would appear in E8?
For
Examiner's
Use
[2]
(c) Column F was added to the spreadsheet to show each person’s ideal weight. This is
calculated using twenty times the square of a person’s height.
What formula needs to be placed in F2?
[1]
9
(a) Give a suitable application for each of the following data capture devices:
barcode reader
radio frequency identification (RFID) reader
magnetic stripe reader
[3]
(b) State two different validation checks and give an example of their use. Each example
should be different.
Check 1
Use
Check 2
Use
[4]
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4
10 (a) Complete the truth table for the following logic circuit, which is made up of NAND
gates:
A
B
X
C
A
B
C
0
0
0
0
0
1
0
1
0
0
1
1
1
0
0
1
0
1
1
1
0
1
1
1
X
[4]
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Examiner's
Use
.
360
5
(b) Name two other types of logic gate and complete their associated truth tables:
Gate 1:
For
Examiner's
Use
Gate 2:
A
B
0
X
A
B
0
0
0
0
1
0
1
1
0
1
0
1
1
1
1
X
[4]
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6
11 A room in a house is fitted with a computerised intruder alarm system:
window
For
Examiner's
Use
= infra red sensors
= pressure sensors
door
(a) (i) Describe how the sensors and computer would be used to detect intruders.
(ii) Describe how the system warns that an intruder has been detected.
[4]
(b) It is decided to automatically close door and window shutters if an intruder is detected.
What additional processing and hardware would be needed?
[2]
(c) Name another sensor that could have been used in this intruder alarm system.
[1]
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7
(d) What measures could be taken to stop or minimise the number of false alarms?
For
Examiner's
Use
[2]
12 (a) John has bought a 4 Gbyte MP3 player.
(You may assume: 1 byte = 8 bits, 1 Mbyte = 1024 kbytes and 1Gbyte = 1024 Mbytes)
(i) We can assume that each song lasts 3 minutes and is recorded at 128 kbps
(kilobits per second).
How much memory is required per song?
[2]
(ii) Using your answer in (i), how many songs can be stored on John’s MP3 player?
[2]
(b) John also bought a device for recording television programmes. It allows him to record
a programme at the same time as he is watching an earlier recording.
Describe how such a system would work.
[3]
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8
13 Look at these two pieces of code:
A:
CLC
LDX
loop: LDA
ADC
STA
INX
CPX
BNE
#0
A,X
B,X
C,X
B: FOR Loop
INPUT
Sum =
PRINT
NEXT
For
Examiner's
Use
= 1 TO 4
Number1, Number2
Number1 + Number2
Sum
#16
loop
(a) Which of these pieces of code is written in a high-level language?
[1]
(b) Give one benefit of writing code in a high-level language.
[1]
(c) Give one benefit of writing code in a low-level language.
[1]
(d) High-level languages can be compiled or interpreted.
Give two differences between a compiler and an interpreter.
1
2
[2]
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9
14 A ship at sea uses Global Positioning System (GPS) technology to navigate.
For
Examiner's
Use
(a) Describe how GPS technology is used to help the ship’s navigation.
[4]
(b) Describe two benefits to the ship’s personnel through using GPS technology.
1
2
[2]
(c) How should the ship’s satnav device give navigation instructions to the ship’s
personnel?
[1]
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0
15 An estate agent advertises houses for sale. The customer enquiries for a 7-day working
week are entered weekly into a computer.
For
Examiner's
Use
Write an algorithm, using pseudocode or a program flowchart only, which:
•
•
•
•
inputs the number of customer enquiries each day,
inputs the house price each customer enquires about,
outputs how many customers enquired each day about houses costing less than
$100 000,
outputs the percentage of all enquiries made during the week about houses costing
more than $500 000.
[6]
Permission to reproduce items where third party owned material protected by copyright is included has been sought and cleared where possible. Every
reasonable effort has been made by the publisher (UCLES) to trace copyright holders, but if any items requiring clearance have unwittingly been included, the
publisher will be pleased to make amends at the earliest possible opportunity.
University of Cambridge International Examinations is part of the Cambridge Assessment Group. Cambridge Assessment is the brand name of University of
Cambridge Local Examinations Syndicate (UCLES), which is itself a department of the University of Cambridge.
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UNIVERSITY OF CAMBRIDGE INTERNATIONAL EXAMINATIONS
GCE Ordinary Level
MARK SCHEME for the May/June 2012 question paper
for the guidance of teachers
7010 COMPUTER STUDIES
7010/12
Paper 1, maximum raw mark 100
This mark scheme is published as an aid to teachers and candidates, to indicate the requirements of
the examination. It shows the basis on which Examiners were instructed to award marks. It does not
indicate the details of the discussions that took place at an Examiners’ meeting before marking began,
which would have considered the acceptability of alternative answers.
Mark schemes must be read in conjunction with the question papers and the report on the
examination.
• Cambridge will not enter into discussions or correspondence in connection with these mark schemes.
Cambridge is publishing the mark schemes for the May/June 2012 question papers for most IGCSE,
GCE Advanced Level and Advanced Subsidiary Level syllabuses and some Ordinary Level
syllabuses.
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Mark Scheme: Teacher version
GCE O LEVEL – May/June 2012
Syllabus
7010
Paper
12
Any three from:
– fact finding
– feasibility study
– analysis
– design
– testing
– documentation/technical documentation/user guide
– implementation/installation
– evaluation
– maintenance
[3]
email
advantages (one from:)
– easier to send attachments
– easier/faster to type
– can format text
– cheaper to send an email
disadvantage (one from:)
– need to buy computer equipment
– computer equipment not as portable as mobile phone
– need a broadband connection/modem/Internet access
– need account for emails
– can send a virus
mobile phones
advantages (one from:)
– completely portable method/can be used on the move
– more people have mobile phones
– use of predictive texting
– cheaper to buy a phone
disadvantage (one from:)
– can’t send large documents/files/limited number of characters
– phone charges for sending messages are relatively high
– phone charges for sending messages overseas are high
– slow to key in messages/small keyboard
– often out of range of signal/poor signal
– smaller screens
3
[4]
Any five from:
– viruses
– hacking
– cookies
– pharming
– phishing
– spyware
– tapping into unsecured wifi network/war driving
– shoulder surfing/over-the-shoulder observation of the Internet user’s credentials/user name
and password
[5]
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Mark Scheme: Teacher version
GCE O LEVEL – May/June 2012
Syllabus
7010
Paper
12
(a)
Printing documents in a
factory environment which is
dusty and damp
3D printer
High quality printing of
30000 colour booklets
per day
Dot matrix printer
Producing prototypes in
resin of a new design
Colour inkjet printer
Producing a colour poster
Colour laser printer
[4]
(b) 3D printer
– capable of producing solid objects
– cheaper than making a working model (by conventional methods)
– works with CAD
dot matrix printer
– can work in harsh environments
– (since in a factory,) noise levels are not important
– quality of printout not important
– robust printer
colour inkjet printer
– suited to low volume
– good/photographic quality printing
colour laser printer
– fast for volume printing
[4]
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Mark Scheme: Teacher version
GCE O LEVEL – May/June 2012
Syllabus
7010
Paper
12
(a) Any three from:
– wire frame
– 2D / 3D modelling
– library of parts which can be used in new drawings
– validation / verification of designs against original specification
– ability to link with computer-aided manufacture (CAM)
– facility to calculate the mass of the actual object once built
– facility to calculate the cost of producing the article
– features such as rotation, colour, zoom, etc.
– simulation of designs (without the need to build a prototype)
– create engineering drawings from solid models
– import and export to allow the exchange of data with other software packages
– kinematics (i.e. check moving parts in assemblies don’t interfere with each other)
– automatic routing of cables and hoses
[3]
(b) Any three from:
– (very) large screens/monitors
– plotters to draw scale and full size drawings
– 3D printers
– CAM machinery/CNC lathe
[3]
(c) Any two health risks and any one safety risk from:
health risks
– RSI from repeated/long continuous use of a keyboard/repeated clicking on a mouse
– back/neck ache from bad posture/incorrect chair position
– headaches caused by glare from monitors
– eye strain caused by glare from monitors/poor lighting
– dry eye caused by staring at screen without blinking
– respiratory problems etc. caused by ozone/toner particulates emitted from a laser printer
safety risks
– electrocution e.g. bare wires, drinks near computers, etc.
– trip hazards from trailing cables
– heavy equipment falling due to failure of inadequate desks, work stations etc.
– fires from short circuits/over-heating equipment
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Mark Scheme: Teacher version
GCE O LEVEL – May/June 2012
Page 5
6
Syllabus
7010
Paper
12
(a)
M
T
S
C
D
32
1
0
1
1
16
32
32
2
8
0
32
3
0
4
8
40
4
1
2
4
44
5
1
1
0
44
6
0
1
45
7
1
(1 mark)
(1 mark)
(1 mark)
(1 mark)
[4]
7
(b) converting binary number into equivalent base 10 number
[1]
(c) 60
[1]
(a) (i) Any one from:
– sound card and/or speakers
– possibly F1 key is faulty
[1]
(ii) Any two from:
– ask a further series of questions
– based on responses of the user
– reference to knowledge base/rules base/explanation system/inference engine
[2]
(iii) Any one from:
– % probability of identified fault found
– advice on how to correct fault
– change the speakers/sound card/keypad
[1]
(b) Any three from:
– knowledge base
– rules base
– inference engine
– expert system shell
– explanation system
[3]
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Mark Scheme: Teacher version
GCE O LEVEL – May/June 2012
Page 6
Syllabus
7010
Paper
12
(c) RAM
– to store data/programs/parts of operating system in use
– to store data that can be changed
ROM
– where operating system/bios is stored
– where data that starts up the system is stored
8
[2]
(a) –1 mark for each different error
D
1
bmi
2
= B2/(C2*C2)
OR
= B2/C2^2
3
= B3/(C3*C3)
OR
= B3/C3^2
4
= B4/(C4*C4)
OR
= B4/C4^2
5
= B5/(C5*C5)
OR
= B5/C5^2
6
= B6/(C6*C6)
OR
= B6/C6^2
7
= B7/(C7*C7)
OR
= B7/C7^2
[2]
(b) (i) normal (correct spelling only)
[1]
(ii) = SUM(D2:D7)/6 or
= AVERAGE(D2:D7) or
= (D2 + D3 + D4 + D5 + D6 + D7)/6
[1]
(iii) = IF(D8 < 18.5, “underweight”, IF(D8 > 25, “overweight”, “normal”))
< - - - - - - - 1 mark - - - - - - - > <- - - - - - - - - - 1 mark - - - - - - - - - >
[2]
(c) = 20 * C2 * C2
OR
= 20 * C2 ^ 2
[1]
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Page 7
9
Syllabus
7010
Paper
12
(a) barcode reader
e.g. (any reasonable application these are just examples)
– stock control
– library loans
– Point Of Sale system
– tracking systems
– itemised billing
RFID
e.g. (any reasonable application these are just examples)
– identifying/tracking individual items e.g. livestock, vehicles
magnetic stripe
e.g. (any reasonable application these are just examples)
– security cards (e.g. hotel room keys)
– credit/debit/smart cards/ATMs/banking
– loyalty cards
[3]
(b) 1 mark for naming validation check + 1 mark for example of its use (the two must match up)
length check
– check if an id number is exactly 8 characters long
range check
– check if a person’s age is in the range 11 to 19
limit check
– check if salary paid greater than 0
character/type
– check if a telephone number contains digits only
consistency check – return flight date after outbound flight date
format check
– check if a date is in the form dd/mm/yyyy
presence check – filling out a form online where a given field MUST have data entered
check digit
– ISBN of a book
[4]
10 (a)
A
B
C
X
0
0
0
1
0
0
1
1
0
1
0
0
0
1
1
1
1
0
0
0
1
0
1
0
1
1
0
0
1
1
1
1
(1 mark)
(1 mark)
(1 mark)
(1 mark)
[4]
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Mark Scheme: Teacher version
GCE O LEVEL – May/June 2012
Page 8
Syllabus
7010
Paper
12
(b) 1 mark for correct logic gate + 1 mark for correct associated truth table.
Any two from:
– NOR, AND, OR, XOR (EOR)
A
B
NOR
AND
OR
XOR
0
0
1
0
0
0
0
1
0
0
1
1
1
0
0
0
1
1
1
1
0
1
1
0
[4]
11 (a) (i) Any points from (maximum of 3 marks):
– signals/data supplied by sensors to the computer
– use of ADC
– computer compares data with pre-stored values
– if data beyond/greater than stored limit, intruder has been detected
– monitoring continues until re-set
(ii) Any points from (maximum of 2 marks):
– computer sends signal …
– … to set off siren/buzzer/light/alarm bell/sounds alarm
– use of a DAC
– automatically informs police/security company
Maximum mark: [4]
(b) Any two points from:
– signal sent to …
– … motors
– … actuators
[2]
(c) Any one point from:
– motion
– light
– sound
– temperature
[1]
(d) Any two points from:
– store realistic values in memory/adjust sensitivity
– use 2 different sensors to monitor the same parameter (e.g. sound sensor and infra-red
sensor to monitor intruder)
– fully/regularly test system once installed
– increase fault tolerance by use of redundant sensors and computers
[2]
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Mark Scheme: Teacher version
GCE O LEVEL – May/June 2012
Page 9
Syllabus
7010
Paper
12
12 (a) (i) 3 minutes = 180 seconds
each song = 180 * 128
= 23 040 kbits
number of bytes = 23 040/8 = 2880 kbyte
= 2.8(125) Mbyte
[2]
(ii) 4 Gbyte = 4 * 1024 = 4 096 Mbyte
therefore, number of songs = 4 096/2.8125 = 1456 songs
[2]
(b) Any three points from:
– uses hard disk/disk pack (2 to 5 disks)
– each disk surface has a R/W head
– use of read and write buffers
– R/W operation is faster than general data transfer rate …
– … therefore simultaneous read/write operations can occur
– description of how a DVD-RAM works
– concentric tracks allow R/W at the same time
– fast R/W operation
[3]
13 (a) code B
[1]
(b) Any one from:
– no need to understand workings of a computer
– easier to understand for programmer/closer to English
– much easier to debug
– much easier to test
– one to many when writing commands
– not machine specific/portable
[1]
(c) Any one from:
– can address memory addresses directly
– no need for compilers/interpreters
– shorter code/code requires less storage/RAM
– can (be written to) run faster
[1]
(d) –
–
–
–
–
compiler produces object code / interpreter doesn’t produce object code
compiler translates whole program in one go / interpreter translates and executes line at
a time
compiler produces list of all errors / interpreter produces error message each time an
error encountered
compiler produces “stand alone code” / interpreter doesn’t produce “stand alone code”
compilation process is slow but resultant code runs very quickly / interpreted code runs
slowly
[2]
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Mark Scheme: Teacher version
GCE O LEVEL – May/June 2012
Syllabus
7010
Paper
12
14 (a) Any four points from:
– satellites transmit signals (to sat nav computer in the ship)
– computer receives/interprets these signals
– system depends on very accurate timing/use of atomic clocks
– each satellite transmits data including location and time
– computer in ship calculates its position based on at least 3 satellites
– at least 24 satellites in operation at a given time
– position of ship is known within 1 metre
– refer to triangulation:
satellite 1
satellite 2
Exact
location
of ship
satellite 3
[4]
(b) Any two benefits from:
– safer (can avoid known risks, identify safe harbour etc.)
– more accurate navigation
– can still navigate at night even under full cloud cover etc.
– the ship automatically transmits location 24/7
– … if accident occurs, ship’s exact location is known
– estimate time of arrival
[2]
(c) Any one from:
– output on LCD screen showing location in relation to known hazards etc.
– animation display (similar to a radar screen)
– verbal instructions
[1]
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Mark Scheme: Teacher version
GCE O LEVEL – May/June 2012
Syllabus
7010
15 sample program:
total2 = 0: totalenquiries = 0
for day = 1 to 7
input enquiries
total1 = 0
totalenquiries = totalenquiries + enquiries
for i = 1 to enquiries
input cust enquiry
if cust enquiry < 100000 then total1 = total1 + 1
if cust enquiry > 500000 then total2 = total2 + 1
next i
print total1
next day
percent = (total2/totalenquiries) * 100
print percent
Paper
12
(1 mark)
(1 mark)
(1 mark)
(1 mark)
(1 mark)
(1 mark)
(1 mark)
(1 mark)
(1 mark)
marking points
•
initialisation of weekly total (total2) and total enquiries outside first loop
•
correct first loop (controlling the number of days i.e. 7)
•
input number of enquiries + control of the central loop
•
initialisation of daily total inside first loop (total1)
•
correct input of customer enquiry (inside second loop)
•
check how many enquiries < 100000 and increment total
•
check how many enquiries > 500000 and increment total
•
calculation of total enquiries and percentage enquiries
•
BOTH outputs in the correct place
[6]
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UNIVERSITY OF CAMBRIDGE INTERNATIONAL EXAMINATIONS
General Certificate of Education Ordinary Level
*0183246430*
7010/11
COMPUTER STUDIES
May/June 2013
Paper 1
2 hours 30 minutes
Candidates answer on the Question Paper.
No Additional Materials are required.
READ THESE INSTRUCTIONS FIRST
Write your Centre number, candidate number and name on all the work you hand in.
Write in dark blue or black pen.
You may use a soft pencil for any diagrams, graphs or rough working.
Do not use staples, paper clips, highlighters, glue or correction fluid.
DO NOT WRITE IN ANY BARCODES.
Answer all questions.
No marks will be awarded for using brand names of software packages or hardware.
At the end of the examination, fasten all your work securely together.
The number of marks is given in brackets [ ] at the end of each question or part question.
For Examiner's Use
This document consists of 20 printed pages.
IB13 06_7010_11/FP
© UCLES 2013
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2
1
Name a suitable sensor for each of the following applications.
Choose a different sensor in each application.
For
Examiner's
Use
(i) control of a central heating system
(ii) operation of automatic doors
(iii) detection of intruders
(iv) monitoring of a greenhouse environment
[4]
2
Name two different types of loop structure in a typical programming language.
Give an example of how ten numbers could be input using the named loop.
Name of type of loop structure
Example
Name of type of loop structure
Example
[6]
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3
3
(a) Which of the following activities should always be regarded as security risks to
computer systems?
Indicate by ticking () the Yes or No column.
Activity
Yes
For
Examiner's
Use
No
chat rooms
cookies
pharming
virus
VoIP
[2]
(b) State what is meant by the five computer terms in the table.
chat rooms
cookies
pharming
virus
VoIP
[5]
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4
4
(a) Name the following types of network topologies:
(i)
For
Examiner's
Use
(ii)
[2]
(b) Give one benefit and one drawback of networking computers.
Benefit
Drawback
[2]
(c) Many networks are known as LAN or WAN.
Give one feature of each type of network.
LAN
WAN
[2]
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5
5
Name a suitable hardware device to enable automatic data capture in each of the following
applications. Each device must be different.
Application
For
Examiner's
Use
Hardware device
automatic stock control system in a
supermarket
keeping track of the livestock on a large
farm
input data into a computer using speech
recognition
[3]
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6
6
Animation using computer systems involves many stages. The diagram below shows a
number of descriptions and terms used in computer animation.
By drawing arrows, connect the correct description to the animation term.
generating intermediate frames between two
images to give the appearance of movement
morphing
special effect that changes one image into
another image (for example, the special effect
of a person slowly turning into an animal)
rendering
generating a final completed 3D image from a
given 2D model by the use of software
tweening
very simple drawing made up of lines, circles
and dots used to depict a character (for
example, a human being)
key frames
a variable controlling the position of part of an
animated character (for example, to control
the changes in a facial expression)
stick figure
drawings that define the starting point and
end point of any smooth transition in
animation
avar
[5]
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Examiner's
Use
383
7
7
Which five computer terms are being described below?
(i) typing in the same data twice and the computer checks both sets of data to see if
they exactly match
For
Examiner's
Use
(ii) signal sent from a printer requesting attention from the processor; this causes a
temporary break in the execution of whatever the processor is doing
(iii) exchange of signals between two devices to ensure synchronisation when
communication starts
(iv) temporary storage area in a printer that holds data waiting to be printed
(v) count of the number of bits before transmission which is sent with the transmission
so that the receiver can check to see whether the same number of bits have
arrived
[5]
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8
8
A company has set up a website to advertise and show houses for sale.
A customer can get access to an online interactive map and can also take a tour around the
house.
(a) Describe three features you would expect to see on an interactive map.
1
2
3
[3]
(b) (i) Name the type of computer technology that enables a tour of the house to take
place using a website.
[1]
(ii) What three features would you expect to see on the website which allows a
customer to take this tour?
1
2
3
[3]
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385
9
9
An expert system has been set up to help diagnose faults in car engine management
systems.
For
Examiner's
Use
(a) One component is an interactive user interface.
Name three other components in a typical expert system.
1
2
3
[3]
(b) Identify two of the features you would expect to see in a typical interactive user
interface supplied with an expert system.
1
2
[2]
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10
10 (a) (i) Complete the truth table for the logic circuit which is made up of NAND gates only.
A
X
B
Working space
A
B
0
0
0
1
1
0
1
1
X
[2]
(ii) What single logic gate has the same function as the above logic circuit?
[1]
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Examiner's
Use
387
11
(b) (i) Complete the truth table for the logic circuit.
For
Examiner's
Use
A
AND
OR
B
X
AND
OR
C
Working space
A
B
C
0
0
0
0
0
1
0
1
0
0
1
1
1
0
0
1
0
1
1
1
0
1
1
1
X
[4]
(ii) What could replace the whole logic circuit?
[1]
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12
11 Letters from the Greek alphabet are to be transferred to a computer system. Each letter can
be represented on an 8 by 8 grid. Each column has a value from 1 to 128.
The value of each row is stored in a table. The values in the column headings are used to
work out the value for each row (e.g. in our example, row 8 has the value 64 + 32 + 4 + 2 =
102).
Thus, in the example below, the letter (π) is stored as:
128 64 32 16
8
4
2
1
row
1
2
3
4
5
6
7
8
value
255
255
102
102
102
102
102
102
(a) What values would be stored in the table for the Greek character (Σ)?
128 64 32 16
8
4
2
1
row
1
2
3
4
5
6
7
8
value
[4]
(b) Draw the character formed from the following value table:
row
1
2
3
4
5
6
7
8
value
146
146
84
84
56
16
16
16
128 64 32 16
8
4
2
1
[4]
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Examiner's
Use
389
13
12 A database was set up to compare oil companies. A section of the database is shown
below:
Code
AR
GZ
KO
OS
SD
SN
ST
SU
WP
Name of
company
Arrows
Gazjeti
Konoco
Oilbras
Sand Oil
Southern Oil
Static Oil
Summation
Wasp Petrol
No of
employees
60 000
35 000
40 000
56 000
102 000
50 000
80 000
70 000
90 000
No of
countries
30
4
22
11
51
15
31
40
44
Head
office
Americas
Asia
Americas
Americas
Europe
Americas
Americas
Europe
Europe
Profits
(billion $)
8.0
5.0
10.0
4.0
12.0
11.0
10.0
9.0
15.0
For
Examiner's
Use
Share
price ($)
39.00
44.50
18.55
59.60
15.30
10.90
52.05
30.40
92.80
(a) How many fields are there in each record?
[1]
(b) The following search condition was entered:
(No of countries < 30) AND (Head office = “Americas”)
Using Code only, which records would be output?
[2]
(c) What search condition is needed to find out which oil companies have a share price
less than $50 or whose profits were greater than 8 billion dollars?
[2]
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14
13 A customer uses Internet banking. To gain access to their account they need:
•
•
•
an 8-digit ID
a 4-digit PIN
a 10-character password
They will be asked to type in their ID, then 3 digits from their PIN and finally 3 characters
from their password. Three attempts at the ID are allowed, but only one attempt at the PIN
and at the password.
The flowchart on the next page shows the access process described above. However, most
of the stages have been omitted.
Complete the flowchart, using item number only, from the list of items given.
Item
number
© UCLES 2013
Item description
1
access to account allowed
2
are any characters in the password
incorrect?
3
are any digits in the ID incorrect?
4
are any digits in the PIN incorrect?
5
generate three random digits from
the PIN
6
generate three random characters
from the password
7
input the required three digits from
the PIN
8
is number of digits < 8
or number of digits > 8?
9
is X > 2?
10
output “access to account denied”
11
X=X+1
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15
For
Examiner's
Use
START
X=0
INPUT
8-digit ID
END
Yes
No
Yes
No
Yes
No
Yes
No
INPUT
3 characters
from password
Yes
No
END
[6]
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16
14 An aeroplane uses three separate computer systems to monitor and control the flight
process while in auto pilot mode.
(a) Explain the advantages of using three computers rather than just one.
[2]
(b) Sensors are used to measure air speed. The readings are sent to the three computers.
Describe how the sensors and computers are used to control the aeroplane’s speed in
auto pilot mode.
[4]
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Examiner's
Use
393
17
(c) The aeroplane uses GPS (global positioning system) technology to navigate to its
destination.
For
Examiner's
Use
(i) How does GPS link with the computers to ensure the correct flight path (for
example, direction) is maintained?
[3]
(ii) Give one benefit and one drawback of using GPS.
benefit
drawback
[2]
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18
15 A spreadsheet was set up to allow customers to work out their monthly payments when
borrowing money from a bank. The customer inputs data in column B.
The spreadsheet is as follows:
A
1
B
C
Interest Calculator
20 000
2
INPUT PRICE OF GOODS
3
INPUT YOUR DEPOSIT
4
AMOUNT OF MONEY TO BORROW
5
INPUT % INTEREST RATE
6
INPUT NUMBER OF YEARS
7
INTEREST TO PAY
8
YOUR MONTHLY REPAYMENTS
5 000
15 000
8.0
0.08
4
4800
412.50
(a) Cell C4 contains the amount of money to borrow.
What formula must be in cell C4?
=
[1]
(b) Cell C5 contains the % interest rate as a decimal (for example, 8% shows as 0.08).
What formula must be in cell C5?
=
[1]
(c) Cell C7 contains interest to pay which is found from
amount of money borrowed × interest rate as a decimal × number of years.
What formula must be in cell C7?
=
[1]
(d) Cell C8 contains the monthly repayment which is found from
sum of the amount borrowed and interest to pay
divided by total number of months.
What formula must be in cell C8?
=
© UCLES 2013
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Examiner's
Use
395
19
(e) Give two different validation checks you would use for inputs to cells:
For
Examiner's
Use
B2
B5
[2]
(f) Describe how you would test the spreadsheet to ensure it works correctly.
[2]
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20
16 A small shop uses barcodes which represent 5 digits. The last digit is used as a check digit.
For example:
a
0
b
1
c
2
d
3
For
Examiner's
Use
e
4
The check digit (e) is found by:
•
•
•
•
•
multiplying the first and third digits (i.e. a and c) by 3
multiplying the second and fourth digits (i.e. b and d) by 2
adding these four results together to give a total
dividing this total by 10
remainder is check digit (e)
Write an algorithm, using pseudocode or flowchart only, which
•
•
•
inputs 100 five-digit barcodes in the form a, b, c, d, e
re-calculates the check digit for each number and checks whether the input check digit
(e) is correct
outputs the number of barcodes which were entered correctly
[5]
Permission to reproduce items where third party owned material protected by copyright is included has been sought and cleared where possible. Every
reasonable effort has been made by the publisher (UCLES) to trace copyright holders, but if any items requiring clearance have unwittingly been included, the
publisher will be pleased to make amends at the earliest possible opportunity.
University of Cambridge International Examinations is part of the Cambridge Assessment Group. Cambridge Assessment is the brand name of University of
Cambridge Local Examinations Syndicate (UCLES), which is itself a department of the University of Cambridge.
© UCLES 2013
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CAMBRIDGE INTERNATIONAL EXAMINATIONS
GCE Ordinary Level
MARK SCHEME for the May/June 2013 series
7010 COMPUTER STUDIES
7010/11
Paper 1, maximum raw mark 100
This mark scheme is published as an aid to teachers and candidates, to indicate the requirements of
the examination. It shows the basis on which Examiners were instructed to award marks. It does not
indicate the details of the discussions that took place at an Examiners’ meeting before marking began,
which would have considered the acceptability of alternative answers.
Mark schemes should be read in conjunction with the question paper and the Principal Examiner
Report for Teachers.
Cambridge will not enter into discussions about these mark schemes.
Cambridge is publishing the mark schemes for the May/June 2013 series for most IGCSE, GCE
Advanced Level and Advanced Subsidiary Level components and some Ordinary Level components.
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398
Mark Scheme
GCE O LEVEL – May/June 2013
Syllabus
7010
Paper
11
A different sensor is needed for each application
(i) central heating system
– temperature sensor
(ii) automatic doors
– pressure sensor/pad
– light sensor
– infra red sensor
(iii) detection of intruders
– pressure sensor/pad
– light sensor
– infra red sensor
– sound/acoustic sensor
(iv) greenhouse monitoring
– temperature sensor
– moisture/humidity sensor
– light sensor
– pH sensor
– CO2/O2 (levels) sensor
2
[4]
1 mark for name of loop structure + 1 mark for correct loop structure including initialisation + 1
mark for correct input inside loop:
for (… to … next) loop
example: for x = 1 to 10
input number
next x
repeat (… until) loop
example: c = 0
repeat
input number
c=c+1
until c > 9 (or equivalent)
while (… endwhile/wend) loop
example: c = 0
while c <> 10 do
input number
c=c+1
endwhile
[6]
© Cambridge International Examinations 2013
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Mark Scheme
GCE O LEVEL – May/June 2013
Syllabus
7010
Paper
11
(3) (a) 2 marks minus 1 for each error.
activity
Yes
No
chat rooms
cookies
pharming
virus
VoIP
[2]
(b) 1 mark per description
chat rooms
– place for online conversations
– use instant messaging
– to allow communications in real time
– users register and choose user name and password
– log onto enter chat room using user name and password
– list of people currently in room will be alerted as soon as new person enters room
cookies
– small files sent to user’s computer when visiting a website
– stores information about user which is accessed every time user visits that website
– lets website know who you are/past visitor
pharming
– malicious code installed on a user’s computer/web server
– misdirecting the user(s) to a bogus/fake fraudulent website
– can use domain name poisoning
virus
– programs that replicate themselves
– designed to disrupt computer system
– delete/alter/corrupt files
VoIP
– Voice over Internet Protocol
– system that allows user to talk to another user using the Internet
– can use USB phone or head set (microphone and headphones)
– requires fast broadband connection to work
– can also combine with webcam and instant messaging
[5]
© Cambridge International Examinations 2013
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Mark Scheme
GCE O LEVEL – May/June 2013
Syllabus
7010
Paper
11
(4) (a) (i) ring
[1]
(ii) star
[1]
(b) 1 mark for benefit and 1 mark for drawback
benefit
– share resources such as hardware e.g. printer, software
– easier to monitor what users are doing
– easier communication between users
drawback
– greater risk of viruses
– greater security risk (such as hacking)
– expensive hardware such as servers, cabling, …
– needs management
[2]
(c) 1 mark for LAN feature and 1 mark for WAN feature
LAN
– used over a small geographic area (e.g. one building)
– doesn’t require external telecommunication
WAN
– used over remote/vast geographic area (e.g. continents)
– needs modem, external phone lines, microwaves…
5
[2]
1 mark for each correct device
application
hardware device
automatic stock control system in a
supermarket
barcode reader/scanner/EFTPOS terminal
keeping track of the live stock on a large
farm
barcode/RFID/microchip reader
input data into a computer using speech
recognition
microphone
[3]
© Cambridge International Examinations 2013
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Mark Scheme
GCE O LEVEL – May/June 2013
Syllabus
7010
Paper
11
6
generating intermediate
frames between two images
to give the appearance of
movement
morphing
special effect that changes
one image into another
image (e.g. the special effect
of a person slowly turning
into an alien)
rendering
generating a final completed
3D image from a given 2D
model by the use of software
tweening
very simple drawing made
up of lines, circles and dots
used to depict a character
(e.g. a human being)
key frames
stick figure
variable controlling the
position of part of an
animated character (e.g.
control changes in a facial
expression)
drawings that define the
starting point and end point
of any smooth transition in
animation
avar
[5]
© Cambridge International Examinations 2013
M.Mushtaq
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7
402
Mark Scheme
GCE O LEVEL – May/June 2013
Syllabus
7010
Paper
11
1 mark for each correct term.
(i) verification
[1]
(ii) interrupt
[1]
(iii) handshaking
[1]
(iv) (printer) buffer, RAM
[1]
(v) checksum
[1]
(8) (a) Any three features from:
– road map and satellite views
– superimpose road map and satellite images
– ability to zoom in and zoom out
– arrow keys to move N, S, E and W
– detailed directions to get from customer’s home to the house
– ability to use street name, post code, zip code (etc.) in searches
– “pins” to show exact location of house on the map/hotspot
– local amenities e.g. post office, school etc.
– scale/conversion of miles to kilometres
[3]
(b) (i) virtual reality
[1]
(ii) Any three from:
– zoom in and out
– buttons to navigate between rooms/enter the tour
– arrow keys to rotate through 360º
– print out of rooms
– save houses visited as “favourites”
– choice of area within house to view
[3]
(9) (a) Any three from:
– knowledge base
– inference engine
– rule(s) base
– (expert system) shell
– explanation system
[3]
(b) Any two from:
– yes/no type of questions
– multiple choice questions
– explanations/examples
[2]
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Mark Scheme
GCE O LEVEL – May/June 2013
Page 7
Syllabus
7010
Paper
11
10 (a) (i)
A
0
0
1
1
B
0
1
0
1
X
1
0
0
0
}
}
1 mark
1 mark
[2]
(ii) NOR gate (allow follow through from part (i))
(b) (i)
A
0
0
0
0
1
1
1
1
B
0
0
1
1
0
0
1
1
C
0
1
0
1
0
1
0
1
[1]
}
}
}
}
X
0
1
0
1
0
1
0
1
1 mark
1 mark
1 mark
1 mark
[4]
(ii) input C only
[1]
11 (a)
row
1
2
3
4
5
6
7
8
value
255
192
96
48
96
192
255
0
}
}
}
}
1 mark
1 mark
1 mark
1 mark
[4]
(b) 128 64 32 16
8
4
2
1
}
}
}
}
1 mark
1 mark
1 mark
1 mark
[4]
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Mark Scheme
GCE O LEVEL – May/June 2013
Syllabus
7010
Paper
11
12 (a) 7
[1]
(b) KO, OS, SN
(–1 mark for each error)
(c) (Share price ($) < 50.00)
[2]
OR
(Profits (billion $) > 8.0)
< - - - - - (1 mark) - - - - -> < - - - - - - - (1 mark) - - - - - - - >
(Profits (billion $) > 8.0)
OR
(Share price ($) < 50.00)
< - - - - - (1 mark) - - - - >
< - - - - - - - (1 mark) - - - - - - - >
[2]
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Mark Scheme
GCE O LEVEL – May/June 2013
13
Syllabus
7010
Paper
11
START
X=0
INPUT 8digit id
END
1 mark
10
Yes
11
9
1 mark
No
Yes
8/3
No
Yes
3/8
1 mark
No
5
7
Yes
1 mark
4
No
6
1 mark
INPUT 3
characters from
password
Yes
2
1 mark
No
1
END
[6]
© Cambridge International Examinations 2013
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Mark Scheme
GCE O LEVEL – May/June 2013
Syllabus
7010
Paper
11
14 (a) Any two from:
– if all computers ‘agree’ system works automatically
– if one computer fails, there are still 2 working
– if one computer is faulty, use “majority output” to make decisions
– increases passenger confidence in the system
[2]
(b) Any four points from:
– sensor readings are taken (continuously)
– these are converted to digital (using ADC)
– data/signals sent to the computer
– the computer compares the data received with stored values/computer interprets signals
– if outside acceptable range, computer sends signals
– signals converted to analogue (using DAC)
– fuel to engines is increased/decreased to control aeroplane speed
– if one computer gives a different signal, a warning message is sent
[4]
(c) (i) Any three points from:
– satellite sends/broadcasts signals to earth
– GPS system uses satellite signals to calculate position of aeroplane
– …..data from at least three satellites needed to calculate this position
– satellites use atomic clocks to ensure very accurate timing
– each satellite transmits data giving its position and time
– computer compares calculated position supplied by GPS system with flight path …
– … if aeroplane off course, then computer sends signals …
– … and rudder settings are changed (using motors) to control direction
– if aeroplane is on course, no action is taken
– direction checking is carried out continuously
[3]
(ii) 1 mark for benefit and 1 mark for drawback
benefit
– estimate time of arrival at destination/remaining flight time
– location of alternative airports in case of emergency
– more accurate flight path maintained
– more efficient fuel costs since fewer course corrections are made
drawback
– if weather is bad, GPS and computer won’t automatically “steer around the problem”
– loss of satellite signal could lead to wrong direction/decision making
[2]
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Mark Scheme
GCE O LEVEL – May/June 2013
Syllabus
7010
Paper
11
15 (a) B2 – B3
[1]
(b) B5/100 or B5*1%
[1]
(c) C4 * C5 * B6
[1]
(d) (C4 + C7)
/ (B6 * 12)
< 1 mark > < 1 mark >
[2]
(e) B2
– check for negative numbers
– check for numbers only (character/type check)
– presence check
– range check
B5
– range check
– character/type check
– presence check
(validation checks must be DIFFERENT for each part of question)
[2]
(f) Any two points from:
– input data with known results
– compare output with known results
– use data to check if validation rules work
– use of normal and abnormal and extreme data
– check deposit < price
[2]
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Mark Scheme
GCE O LEVEL – May/June 2013
Page 12
Syllabus
7010
16 marking points:
– set total of barcodes entered correctly to zero (initialisation, e.g. match = 0 below)
– input 100 numbers (correct loop structure)
– input 5 digits of the barcode (a, b, c, d and e) INSIDE a loop
– find total value using barcode formula given
– method for finding remainder
(e.g. subtract 10 from total (1 mark) using a loop (1 mark) until total < 10)
– finding out how many correct barcodes were input
– correct output (OUTSIDE loop – must have a loop to get mark)
Paper
11
1 mark
1 mark
1 mark
1 mark
2 marks
1 mark
1 mark
example of suitable coding:
match = 0
1 mark
for number = 1 to 100
1 mark
input a, b, c, d, e
1 mark
total = (a * 3) + (c * 3) + (b * 2) + (d * 2)
1 mark
repeat
total = total – 10
2 marks
until total < 10
if total = e then match = match + 1
1 mark
next number
print match
1 mark
[5]
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UNIVERSITY OF CAMBRIDGE INTERNATIONAL EXAMINATIONS
General Certificate of Education Ordinary Level
*6932410883*
7010/12
COMPUTER STUDIES
May/June 2013
Paper 1
2 hours 30 minutes
Candidates answer on the Question Paper.
No Additional Materials are required.
READ THESE INSTRUCTIONS FIRST
Write your Centre number, candidate number and name on all the work you hand in.
Write in dark blue or black pen.
You may use a soft pencil for any diagrams, graphs or rough working.
Do not use staples, paper clips, highlighters, glue or correction fluid.
DO NOT WRITE IN ANY BARCODES.
Answer all questions.
No marks will be awarded for using brand names of software packages or hardware.
At the end of the examination, fasten all your work securely together.
The number of marks is given in brackets [ ] at the end of each question or part question.
For Examiner's Use
This document consists of 20 printed pages.
IB13 06_7010_12/FP
© UCLES 2013
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2
2
Four types of data storage media and four descriptions are shown in the table below.
Tick () the appropriate boxes in the table to match each data storage medium to its most
suitable description.
CD-ROM
DVD-RAM
fixed hard
disk
memory stick
storage medium where
data can only be read
and not altered
portable medium which
allows transfer of data
between computers
memory where operating
systems and applications
software are usually
stored
medium which allows
recording and playback
to occur at the same time
[4]
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3
3
Three common devices are listed below:
•
•
•
For
Examiner's
Use
MP3 player
digital camera
mobile phone
(a) Choose one of the above devices.
Describe the type of internal memory the device uses.
Describe how data is transferred from the device to a computer.
Device
Type of internal memory used
Method of transferring data to a computer
[2]
(b) Modern mobile phones include a digital camera and an MP3 player.
(i) Give one disadvantage when compared to a dedicated MP3 player.
(ii) Give one disadvantage when compared to a dedicated digital camera.
[2]
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4
4
(a) Computer systems can introduce a number of health and safety issues in the office.
Five potential risks are shown below. Indicate by ticking the appropriate column
whether the risk is a health issue or a safety issue.
potential risk
health issue
safety issue
repetitive strain injury (RSI) caused by
excessive clicking of a mouse or typing
trailing wires connected to a computer
system
ozone gas and toner particles produced
during laser printer operation
headaches and eye strain caused by
glare from a computer monitor/screen
electrocution caused by spilling liquids
on a computer system
[5]
(b) Introduction of computer systems can also have an impact on the workers in the office.
Give three potential ways computers can affect the office workers.
1
2
3
[3]
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Examiner's
Use
413
5
5
Five definitions are given on the left hand side of the diagram below. Five computer terms
are shown on the right.
For
Examiner's
Use
By drawing arrows, connect each definition to the correct computer term.
website that allows virtual
communication; user joins a site and
invites friends who, in turn, invite their
own friends
chat room
technology that allows telephone calls
to be made using computer networks,
such as the Internet
social networking
online “place” where a group of people
get together and discuss a number of
topics
tagging
software that allows any user to freely
create and edit a web page using their
own web browser
VoIP
marking, saving and archiving certain
websites or items (such as photos); for
example, it allows users to track and
organise favourite websites or photos
wiki
[4]
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6
6
Five students made the following statements.
For
Examiner's
Use
Explain why each statement is incorrect.
(a) “I always use CD-ROMs to save my data.”
[1]
(b) “The advantage of WiFi in the home is you don’t need the use of a telephone line
connection.”
[1]
(c) “Satellite navigation systems in cars send signals to satellites so that the satellite can
work out where they are.”
[1]
(d) “Sending an email will cause a problem if the recipient is in another time zone where
the time difference is 12 hours.”
[1]
(e) “Video conferencing allows meetings to be called at any time.”
[1]
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7
7
The speed at which a CD spins in a portable music CD player is controlled by sensors and
a small microprocessor.
For
Examiner's
Use
(a) Describe how the sensors and microprocessor are used to control the speed of the
spinning CD.
[4]
(b) Sudden movements can make the CD “skip”.
How can the microprocessor deal with this so that the CD operates correctly?
[2]
(c) Why would an MP3 player not suffer from the same problem?
[1]
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8
8
Expert Systems are made up of a number of components.
For
Examiner's
Use
(a) The diagram below shows four of these components and four definitions.
By drawing arrows, link the four components to their correct definitions:
made up of a series of if … then
statements called inference rules
Inference Engine
provides reasoning mechanism in a
typical expert system
Knowledge Base
presents questions and information to a
user and allows them to input a
response
Rules Base
collection of facts used to solve
problems in an expert system
User Interface
[3]
(b) Describe three of the limitations associated with using Expert Systems.
1
2
3
[3]
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9
9
Thin film technology is becoming increasingly common. This uses material as thin as a
sheet of paper but which acts just like an LCD monitor. A microprocessor is used to control
the device and solid state memories are used to supply the data.
For
Examiner's
Use
(a) Describe two advantages of thin film technology.
1
2
[2]
(b) Describe two applications that could use thin film technology.
1
2
[2]
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10
10 A company uses an intranet which can also communicate with the outside world through
the Internet.
(a) The system uses modems.
What is the purpose of a modem?
[1]
(b) Part of the company’s security strategy is to use a firewall.
Describe two features of a firewall.
1
2
[2]
(c) Connecting to the Internet can cause potential problems.
State two of these problems.
1
2
[2]
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419
11
11 A survey of motorways was carried out and a database was produced. A section of the
database is shown below.
Motorway
ID
Length
(km)
Cars per day
Toll charge
per km ($)
Number of
lanes
M1
100
50 000
0.60
2
M2
210
75 000
0.40
3
M3
180
60 000
0.50
4
M4
40
20 000
0.30
3
M5
25
15 000
0.10
2
M6
100
40 000
0.70
4
M7
30
10 000
0.40
2
M8
150
60 000
0.60
4
For
Examiner's
Use
(a) How many fields and how many records are shown?
(i)
number of fields
(ii)
number of records
[2]
(b) Using Motorway ID only, what would be output if the following search condition was
used?
(Length (km) > 100) AND (Number of lanes > 3)
[1]
(c) What search condition is needed to find the motorways where the number of cars per
day exceeds 50 000 or the toll charge per kilometre is greater than $0.50?
[2]
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12
12 Study the following flowchart very carefully.
For
Examiner's
Use
START
INPUT A, B, C, D, E
K=0
X=0
is A > B ?
No
K=A
A=B
B=K
X=1
Yes
is B > C ?
No
K=B
B=C
C=K
X=1
Yes
X=0
is C > D ?
No
K=C
C=D
D=K
X=1
Yes
is D > E ?
No
K=D
D=E
E=K
X=1
Yes
Yes
is X = 1 ?
No
OUTPUT
A, B, C, D, E
END
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13
(a) Complete the trace table for this flowchart using the following test data:
For
Examiner's
Use
3, 5, 1, 4, 8
A
B
C
D
E
K
X
[5]
(b) What values are output from the flowchart using the above test data?
[1]
(c) What function is this flowchart carrying out?
[1]
(d) What would happen if the value of X wasn’t set to 0 in the return loop of the flowchart?
[1]
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14
13 A company requests new customers who register online to give the following details:
•
•
•
•
For
Examiner's
Use
name
address
type of credit/debit card
payment card number
All details must be entered.
(a) (i) Describe one suitable different validation check for each field.
name
address
type of credit/debit card
payment card number
[4]
(ii) Which of the four fields could be offered as a drop down box?
Explain.
[2]
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15
(b) Other data required:
•
•
•
For
Examiner's
Use
date of birth
male or female
accept/decline company conditions
Describe suitable input methods for this data.
date of birth
male or female
accept/decline company conditions
[3]
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16
14 Some decorative lights are made up from a cluster of red, blue, green, yellow and white
LEDs.
Each colour is represented by a binary code:
32
1
16
0
8
0
4
0
2
0
1
0
red
0
1
0
0
0
0
blue
0
0
1
0
0
0
green
0
0
0
1
0
0
yellow
0
0
0
0
1
0
white
0
0
0
0
0
1
black (all lights off)
A 6-bit register, R1, stores the 1-values to represent a sequence of colours.
Thus, if R1 contains:
0
1
0
1
0
1
this means the blue, yellow and black colour sequence is stored and displayed in that
order.
The length of time each light is on is set by a binary value in another register, R2:
Thus
0
1
0
means each colour is on for 2 seconds.
(a) The two registers contain the following values.
What is the sequence of coloured lights and the timing for each colour?
R1
0
R2
1
1
0
1
0
1
1
1
sequence of colours
timing
[2]
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425
17
(b) What will the two registers contain if the coloured light sequence is red, green and
black and the timing is 5 seconds?
R1
For
Examiner's
Use
R2
[2]
(c) What is the problem with trying to display green, blue, red in that order?
[2]
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18
15 (a) Draw the logic circuit represented by the logic statement:
For
Examiner's
Use
X = 1 if (B is NOT 1 AND S is NOT 1) OR (P is NOT 1 AND S is 1)
B
S
X
P
[6]
(b) Complete the truth table for the above logic statement.
Working space
B
S
P
0
0
0
0
0
1
0
1
0
0
1
1
1
0
0
1
0
1
1
1
0
1
1
1
X
[4]
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19
16 A large word processor is being developed by first writing a series of modules. These are
then put together to form the final word processor. Testing is done on each module and on
the final word processor. The following flowchart shows how this word processor is
developed. Several of the stages have been omitted.
For
Examiner's
Use
Complete the flowchart, using item number only, from the list of items given.
START
WRITE the
module
Yes
ITEM LIST
Item
Number
No
Yes
No
Item
Description
1
any errors in the module?
2
any more modules to write and test?
3
combine all modules to form final
word processor
4
does final word processor give
expected results?
5
modify final word processor
6
modify the module
7
test module using data with known
outcomes
8
test final word processor using data
with known outcomes
9
write user documentation
No
Yes
END
[5]
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20
17 A country has four mobile phone network operators. Each mobile phone number has eight
digits. The first three digits identify the network operator:
444
555
666
777
For
Examiner's
Use
Yodafone
N2 network
Kofee mobile
Satsuma mobile
Write an algorithm, using pseudocode or flowchart only, which reads 50 000 eight-digit
mobile phone calls made during the day and outputs the number of calls made on each of
the four networks.
[6]
Permission to reproduce items where third party owned material protected by copyright is included has been sought and cleared where possible. Every
reasonable effort has been made by the publisher (UCLES) to trace copyright holders, but if any items requiring clearance have unwittingly been included, the
publisher will be pleased to make amends at the earliest possible opportunity.
University of Cambridge International Examinations is part of the Cambridge Assessment Group. Cambridge Assessment is the brand name of University of
Cambridge Local Examinations Syndicate (UCLES), which is itself a department of the University of Cambridge.
© UCLES 2013
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CAMBRIDGE INTERNATIONAL EXAMINATIONS
GCE Ordinary Level
MARK SCHEME for the May/June 2013 series
7010 COMPUTER STUDIES
7010/12
Paper 1, maximum raw mark 100
This mark scheme is published as an aid to teachers and candidates, to indicate the requirements of
the examination. It shows the basis on which Examiners were instructed to award marks. It does not
indicate the details of the discussions that took place at an Examiners’ meeting before marking began,
which would have considered the acceptability of alternative answers.
Mark schemes should be read in conjunction with the question paper and the Principal Examiner
Report for Teachers.
Cambridge will not enter into discussions about these mark schemes.
Cambridge is publishing the mark schemes for the May/June 2013 series for most IGCSE, GCE
Advanced Level and Advanced Subsidiary Level components and some Ordinary Level components.
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430
Mark Scheme
GCE O LEVEL – May/June 2013
Syllabus
7010
Paper
12
(a) Any two items from the list:
purpose of the system/program/software/package
program listing/coding
programming language used
flowcharts/algorithms/pseudocode
screen (input) formats/layouts
hardware requirements
software requirements
(minimum) memory requirements
known bugs
list of variables (and their meaning)/data dictionary
file structures
sample runs
output formats/layouts
validation rules
meaning of error messages
installation guide
[2]
(b) Any two items from the list:
purpose of the system/program/software/package
how to log in/log out
how to load/run software
how to save/load files
how to do a search
how to sort data
how to print (out documents/files)
how to delete/add/amend records
screen (input) formats/layouts
output formats/layouts
hardware requirements
software requirements
sample runs
meaning of error messages
troubleshooting/help/FAQs
tutorials
installation guide
[2]
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431
Mark Scheme
GCE O LEVEL – May/June 2013
Syllabus
7010
Paper
12
1 mark for each correctly identified use of data storage medium (column):
CD-ROM
storage medium
where data can
only be read
and not altered
DVD-RAM
fixed hard disk
portable
medium which
allows transfer
of data between
computers
memory where
operating
systems and
applications
software are
usually stored
medium which
allows recording
and playback to
occur at the
same time
memory stick
[4]
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432
Mark Scheme
GCE O LEVEL – May/June 2013
Syllabus
7010
Paper
12
(a) 1 mark for type of memory used and 1 mark for data transfer method.
chosen device
MP3 player
digital camera
mobile phone
type of internal memory
method of transferring data
–
–
–
–
–
(NAND) flash memory
solid state memory
type of EEPROM
non-volatile memory
SD card
–
–
–
–
–
–
(NAND) flash memory
solid state memory
type of EEPROM
non-volatile memory
SD card or XD card
–
–
–
–
–
–
(NAND) flash memory
solid state memory
type of EEPROM
non-volatile memory
SD card
–
–
–
–
–
–
–
using USB (port/cable) in
computer
blue tooth/WiFi connection
slot card into computer card
reader
using USB (port/cable) in
computer
blue tooth/WiFi connection
slot card into computer card
reader
using USB (port/cable) in
computer
blue tooth/WiFi connection
slot card into computer card
reader
[2]
(b) (i) Any one disadvantage from:
– memory size in mobile phone is usually much smaller
– many MP3 features (e.g. shuffle) not available on the mobile phone
– track/song can be interrupted by an incoming call on a mobile phone
[1]
(ii) Any one disadvantage from:
– poorer quality of image due to phone’s inferior camera lens/fewer pixels /lower
resolution
– stores fewer pictures
– fewer photographic options
[1]
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433
Mark Scheme
GCE O LEVEL – May/June 2013
Syllabus
7010
Paper
12
(a) 1 mark for each correct health and safety risk identified:
health
issue
potential risk
repetitive strain injury (RSI) caused by excessive
clicking of a mouse or typing
safety
issue
trailing wires connected to a computer system
ozone gas and toner particles produced during laser
printer operation
headaches and eye strain caused by glare from a
computer monitor/screen
electrocution risk caused by spilling liquids on a
computer system
[5]
(b) Any three from:
– loss of work/unemployment
– de-skilling of workers
– need for workers to re-train
– can work from home/remote working
– use of video conferencing rather than face to face meetings
– quieter environment in the office
– more use of “out sourcing” of work (workers become project managers)
– use of computer for non-work related activities (accept an example of this)
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Mark Scheme
GCE O LEVEL – May/June 2013
Syllabus
7010
Paper
12
5
website that allows virtual
communication; user joins a
site and invites friends who,
in turn, invite their own
friends
chat room
technology that allows
telephone calls to be made
using computer networks,
such as the Internet
social networking
on line “place” where a group
of people get together and
discuss a number of topics
tagging
server software that allows
any user to freely create and
edit a web page using their
own web browser
VoIP
marking, saving and
archiving certain web sites or
items (such as photos); it
allows users to track and
organise favourite web sites
and, for example, photos
wiki
[4]
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435
Mark Scheme
GCE O LEVEL – May/June 2013
Syllabus
7010
Paper
12
(a) Any one from:
– not possible to save data on a CD-ROM
– CD-ROMs are read only
– data cannot be altered on a CD-ROM
[1]
(b) Any one from:
– WiFi only connects devices together in the home/connects to router
– still need Internet external connection via telephone network/wires
[1]
(c) Any one from:
– satellites send signals TO (the GPS system in) the car (sat nav)
– GPS device and NOT the satellite works out the cars’ location
[1]
(d) Any one from:
– Messages left in the inbox/stored on server
– and then opens it/reads message at their leisure
[1]
(e) Any one from:
– not true since time zones/differences prevent this
– meetings can be held at short notice (which is very different)
[1]
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436
Mark Scheme
GCE O LEVEL – May/June 2013
Syllabus
7010
Paper
12
(a) Any four points from:
– (light) sensor sends data signals about spinning CD to microprocessor
– the signals/data are converted from analogue to digital (by an ADC)
– microprocessor uses data and “counts” number of CD revolutions per second/calculates
speed of revolution
– this calculated/received value is compared to the value stored in memory
– if the number of revolutions/speed is out of acceptable range microprocessor sends a
signal …
– … and the CD speed is increased/decreased accordingly
– an error message is also sent if the speed is out of range
[4]
(b) Any two points from:
– sensors indicate sudden jolt/movement
– data from CD stored in a temporary memory/buffer
– there is a (2 to 4 second) delay in “real time” playback
– playback is suspended until device is stable again
[2]
(c) Any one from:
– no moving parts e.g. no spinning CDs, solid state
– no “physical” media
[1]
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Mark Scheme
GCE O LEVEL – May/June 2013
Page 9
8
Syllabus
7010
Paper
12
(a)
made up of a series of if …
then statements called
inference rules
Inference Engine
provides reasoning
mechanism in a typical
expert system
Knowledge Base
presents questions and
information to a user and
allows them to input a
response
Rules Base
collection of facts and rules
used to solve problems in an
expert system
User Interface
[3]
(b) Any three from:
–
–
–
–
–
–
–
lack human common sense
cannot make creative responses in unusual/new circumstances
can’t always explain clearly their logic and reasoning
lack a degree of flexibility
not able to recognize when no answer is actually available
do not learn unless the knowledge base/expert system is updated
only give percentage probability that answer could be correct
[3]
© Cambridge International Examinations 2013
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9
438
Mark Scheme
GCE O LEVEL – May/June 2013
Syllabus
7010
Paper
12
(a) Any two from:
– can put the film anywhere (e.g. stick on a curved wall)
– can fit to awkward shapes where rigid screen would be impossible
– can be any size required
– self-contained unit
– use less energy
– less physical space required
[2]
(b) Any two from:
– advertising (e.g. in railway stations, airports, etc.)
– books/magazines/newspapers made out of the thin film
– art (i.e. moving pictures, light shows, etc.)
– any screen application e.g. TV, mobile phone etc.
[2]
10 (a) Any one from:
– allows digital systems to use analogue phone networks
– convert analogue – digital – analogue
– digital signal converted from one form to another (for transmission)
[1]
(b) Any two from:
– blocks unauthorized external users gaining access to the intranet
– blocks programs/software gaining access to Internet from intranet
– filters out certain websites to users of intranet when accessing the Internet
– aids/helps to prevent viruses
– packet inspection/traffic flow monitoring
[2]
(c) Any two from:
– hacking
– viruses/malware
– security issues (pharming, phishing, spyware, etc.)
– access to undesirable web sites
– abuse of computer time by work force
[2]
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Mark Scheme
GCE O LEVEL – May/June 2013
Page 11
Syllabus
7010
Paper
12
11 (a) (i) 5
[1]
(ii) 8
[1]
(b) M3 and M8
only
[1]
(c) (Cars per day > 50 000)
OR
(Toll charge per km ($) > 0.50)
< - - - - - (1 mark) - - - - > < - - - - - - - - - (1 mark) - - - - - - - - - ->
Or
(Toll charge per km ($) > 0.50) OR (Cars per day > 50 000)
< - - - - - - - (1 mark) - - - - - - - > < - - - - - - - (1 mark) - - - - - - ->
[2]
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GCE O LEVEL – May/June 2013
Page 12
Syllabus
7010
Paper
12
12 (a) a
A
3
5
B
5
3
4
8
8
C
1
D
4
E
8
4
1
8
1
3
8
3
4
K
0
3
1
1
3
3
4
5
5
X
0
1
1
1
0
1
1
0
1
0
1
0
< - - - - 1 mark - - - - >< 1 mark >< - - - - 1 mark - - - - > < 1 mark >< 1 mark >
[5]
(b) 8, 5, 4, 3, 1
[1]
(c) SORT/ORDER (descending) routine
[1]
(d) – would continue looping round even when sorting complete
– loop would never end/infinite loop
[1]
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GCE O LEVEL – May/June 2013
Page 13
13 (a) (i) name:
Syllabus
7010
Paper
12
– character/type check
– presence check
address:
– character/type check
– presence check
– use lookup file/database
type of card:
– character/type check
– presence check
– consistency check
– format check
card number:
– length check
– format check
– check digit
– range check
– character/type check
– presence check
(need different validation check for each item)
[4]
(ii) – type of credit/debit card
– limited number of possible options
(b) date of birth
male or female
[2]
–
–
drop down boxes of day, month and year
use of input boxes:
–
calendar object
–
–
–
radio buttons
tick/check boxes
drop down/combo box
accept/decline company conditions
– tick/check boxes
– radio buttons
– drop down/combo box
[3]
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GCE O LEVEL – May/June 2013
Page 14
14 (a) sequence of colours is:
1
0
1
Paper
12
blue
green
white
time delay is:
(b)
Syllabus
7010
7 seconds
0
0
1
<- - - - - - - 1 mark - - - - - - ->
1
0
[2]
1
<- - 1 mark - ->
[2]
(c) – sequence always starts from left to right
– so sequence would still be red, blue then green
[2]
© Cambridge International Examinations 2013
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Marrk Sc
Sche
eme
GC
GCE O LEVEL – Ma
May/June
e 20
013
3
Pa
age
e 15
5
S
Syllab
bus
s
7010
0
Pape
er
12
15
5 (a)
(
1 mar
m rk per corrrec
ct lo
ogic gat
g e
( cce
(Ac
ept otther nota
n atio
on forr lo
ogic
c gates))
[6
6]
( )
(b)
B
S
P
X
0
0
0
1
0
0
1
1
0
1
0
1
0
1
1
0
1
0
0
0
1
0
1
0
1
1
0
1
1
1
1
0
}
}
}
}
[4
4]
© Ca
amb
bridge
e In
nterrnational Ex
xam
minations
s 20
013
3
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Page 16
Syllabus
7010
Paper
12
16
START
WRITE the
module
7
Yes
1
6
1 mark
No
1 mark
Yes
2
No
3
1 mark
8
1 mark
No
4
5
Yes
9
1 mark
END
[5]
© Cambridge International Examinations 2013
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Mark Scheme
GCE O LEVEL – May/June 2013
Page 17
17 marking points:
– initialisation of all the variables
– corrects loop (1 to 50 000)
– input number (INSIDE a loop)
– how to identify the first 3 digits in the input number
– test which of the 4 networks number comes from
– increment appropriate network total (INSIDE a loop)
– addition of some form of error checking
– output totals (OUTSIDE the loop)
Syllabus
7010
Paper
12
1 mark
1 mark
1 mark
1 mark
1 mark
1 mark
1 mark
1 mark
sample coding:
Y = 0: N = 0: K = 0: S = 0
1 mark
for count = 1 to 50 000
1 mark
input number
1 mark
X = number/100 000 000
1 mark
if X > 0.7 then S = S + 1
}
else if X > 0.6 then K = K + 1
else if X > 0.5 then N = N + 1
else if X > 0.4 then Y = Y + 1
}
2
}
marks
}
else print “error in number”
1 mark
next count
print Y, N, K, S
1 mark
[6]
© Cambridge International Examinations 2013
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UNIVERSITY OF CAMBRIDGE INTERNATIONAL EXAMINATIONS
General Certificate of Education Ordinary Level
*9979711302*
7010/12
COMPUTER STUDIES
October/November 2013
Paper 1
2 hours 30 minutes
Candidates answer on the Question Paper.
No Additional Materials are required.
READ THESE INSTRUCTIONS FIRST
Write your Centre number, candidate number and name on all the work you hand in.
Write in dark blue or black pen.
You may use a soft pencil for any diagrams, graphs or rough working.
Do not use staples, paper clips, highlighters, glue or correction fluid.
DO NOT WRITE IN ANY BARCODES.
Answer all questions.
No marks will be awarded for using brand names of software packages or hardware.
At the end of the examination, fasten all your work securely together.
The number of marks is given in brackets [ ] at the end of each question or part question.
For Examiner's Use
This document consists of 20 printed pages.
IB13 11_7010_12/FP
© UCLES 2013
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2
1
Internet security is a major issue for many people. The following is a list of five typical
security issues:
•
•
•
•
•
hacking
pharming
phishing
spyware
viruses
Choose three of these security issues.
For each one, describe the security issue and suggest a way of protecting against it.
Security issue 1
Description of issue
Method of protection
Security issue 2
Description of issue
Method of protection
Security issue 3
Description of issue
Method of protection
[6]
© UCLES 2013
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For
Examiner's
Use
448
3
2
(a) Mobile phones are communication devices. They allow communication via speech or
text messaging.
For
Examiner's
Use
(i) Most mobile phones offer predictive texting.
State what is meant by this term.
[1]
(ii) What two additional functions would you expect to find on a mobile phone?
1
2
[2]
(b) Connecting a USB telephone to a computer allows communication using VoIP
technology.
(i) Give one advantage of using VoIP rather than other telephone systems.
(ii) Give one disadvantage of using VoIP rather than other telephone systems.
(iii) To use VoIP, there is no need to use a USB telephone.
What other hardware could be used to allow verbal communications?
[3]
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4
3
A motor car manufacturer offers various combinations of
•
•
•
For
Examiner's
Use
seat colours
seat materials
car paint colours
A database was set up to help customers choose which seat and paint combinations were
possible.
code
CB
LB
CC
LC
CG
LG
CR
LR
CL
LL
seat material
cloth leather
Y
N
Y
N
Y
N
Y
N
Y
N
N
Y
N
Y
N
Y
N
Y
N
Y
seat
white
colour
black
Y
black
N
cream
N
cream
N
grey
N
grey
N
red
Y
red
Y
lime
N
lime
N
red
car paint colours
black blue green silver
Y
Y
Y
Y
Y
Y
N
N
N
N
Y
N
Y
Y
Y
N
Y
Y
N
Y
Y
N
Y
Y
Y
Y
N
N
Y
Y
Y
N
N
N
Y
N
N
N
N
Y
Y
Y
N
N
Y
Y
Y
Y
N
N
grey
Y
Y
N
Y
N
Y
Y
Y
N
N
(NOTE: N = no, not a possible combination, Y = yes, combination is possible)
(a) How many records are shown in the database?
[1]
(b) The following search condition was entered:
(cloth = “Y”) AND (blue = “Y”)
Using code only, which records will be found?
[2]
(c) A customer wanted to know the possible combinations for a car with leather seats and
either silver or grey paint colour.
What search condition would need to be input?
[2]
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5
(d) A customer decided to buy a green car. He wanted to know which seat colours and
seat materials were not a possible combination with green paint.
For
Examiner's
Use
What search condition would he need to enter?
[1]
(e) Give one advantage of using the codes Y and N in the database rather than using Yes
and No.
[1]
4
(a) Seven hardware items are shown on the right hand side in the diagram below. Three
applications are shown on the left in the diagram.
By drawing arrows, link each application to the appropriate hardware items (each
hardware item must be used once only):
speakers
computer aided design (CAD)
light pen
microphone
video conferencing
spaceball
data goggles
virtual reality
webcam
data gloves
[3]
(b) Name one additional item of hardware used in each of the three applications named in
the above diagram.
CAD
video conferencing
virtual reality
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6
5
Study the following flowchart very carefully.
For
Examiner's
Use
START
count = 1
total = 0
INPUT
a, b, c, d
x=a*3+c*3
y=b*2+d*2
total = x + y
temp = total
temp = temp - 10
No
is temp
< 10?
Yes
OUTPUT
temp
count = count + 1
Yes
© UCLES 2013
is count
<= 2?
No
END
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7
Complete the trace table for the following two sets of data:
For
Examiner's
Use
(i) a = 5, b = 4, c = 1, d = 9
(ii) a = 5, b = 9, c = 4, d = 1
count
total
a
b
c
d
x
y
temp
OUTPUT
[6]
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8
6
A spreadsheet was set up to calculate values of v based on the formula:
For
Examiner's
Use
v=u+a*t
1
2
3
4
5
6
7
8
A
value of u
20
10
30
40
50
20
B
value of a
9.81
9.81
9.81
9.81
9.81
9.81
C
value of t
10
20
40
30
20
50
D
result v
(a) A student typed in = (D2 + B2 * C2) into cell D2.
Why would this formula produce an error message?
[1]
(b) What is the correct formula that should be in cell D2?
=
[1]
(c) If this formula was replicated down to cell D7, what formula would be in D7?
=
[1]
(d) What formula is required in cell D8 to find the highest value of v?
=
[1]
(e) Column B has the same value throughout.
If column B was removed, what would be the new formula in D2?
=
© UCLES 2013
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9
7
A company employs staff who frequently use computer systems.
For
Examiner's
Use
(a) The health and safety of the staff when using computers is very important.
(i) It was discovered that two staff were suffering from RSI in the hands and wrists.
What could cause such problems?
How could this health risk be removed or reduced?
[2]
(ii) Three accidents had been caused by staff tripping over wires in the office.
How could this safety risk be removed?
[1]
(iii) Name another health and safety risk and describe what problem it might cause.
Name of risk
Description of problem
[2]
(b) Before the introduction of computers, the staff used to do all the office tasks (such as
filing) manually.
Describe two ways the introduction of computers might have affected the staff.
1
2
[2]
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10
8
A piece of pseudocode was written to input 1000 positive numbers and then output the
highest and lowest numbers.
10
20
30
40
50
60
70
80
90
highest = 0
lowest = 0
for count = 1 to 100
input number
if number > highest then number = highest
if number < lowest then number = lowest
count = count + 1
next count
print highest, lowest
There are errors in the code.
Locate these errors and suggest a correction.
Error 1
Correction
Error 2
Correction
Error 3
Correction
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Examiner's
Use
456
11
For
Examiner's
Use
Error 4
Correction
[8]
9
Alex sends an email with a number of attachments to his friend, Nicola.
Describe three possible problems Nicola might have when she tries to open these
attachments.
1
2
3
[3]
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12
10 (a) (i) Complete the truth table for the following logic circuit which is made up of NOR
gates only.
A
X
B
Working space
A
B
0
0
0
1
1
0
1
1
X
[2]
(ii) What single logic gate has the same function as the above circuit?
[1]
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Examiner's
Use
458
13
(b) Complete the truth table for the following logic circuit.
For
Examiner's
Use
A
AND
B
NOT
OR
X
AND
C
Working space
A
B
C
0
0
0
0
0
1
0
1
0
0
1
1
1
0
0
1
0
1
1
1
0
1
1
1
X
[4]
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14
11 A denary number can be represented as an 8-bit binary number. For example:
For
Examiner's
Use
27 would be represented as:
128
64
32
16
8
4
2
1
0
0
0
1
1
0
1
1
128
64
32
16
8
4
2
1
0
0
1
1
0
1
1
0
All the bits in the binary number have now been shifted (moved) one place to the left.
(a) What denary number does this now represent?
[1]
(b) What effect did the shift have on the original denary number?
[1]
(c) If the above binary number was shifted another one place to the left, what denary
number would it be equivalent to?
[1]
(d) (i) Represent the denary number 46 as an 8-bit binary number.
128
64
32
16
8
4
2
1
[1]
(ii) Shift this 8-bit binary number 2 places to the left.
What is the denary equivalent?
[1]
(iii) What problem would arise if you tried to shift this 8-bit binary number 3 places to
the left?
[1]
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15
(e) If any 8-bit binary number was shifted one place to the right, what would this be
equivalent to?
For
Examiner's
Use
[1]
12 A shop uses an information screen linked to a computer to allow customers to order goods
directly.
The first screen shows three options:
electrical goods
furniture
stationery
(a) What is the best input device to allow customers to choose one of the three options?
[1]
(b) The customer is then sent to another screen where they have to input:
•
•
•
the goods reference number which is 8 digits long
today’s date which must be in the form dd/mm/yyyy
the customer’s telephone number
For each input give one validation check that should be performed.
A different type of check must be given in each case.
goods reference number
today’s date
telephone number
© UCLES 2013
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16
13 A company advertises its Internet broadband speeds as follows:
•
•
download speed of 128 megabits per second
upload speed of 16 megabits per second
For
Examiner's
Use
(8 bits = 1 byte)
(a) Explain what is meant by the two terms download speed and upload speed.
download speed
upload speed
[2]
(b) Give two advantages of using broadband rather than dial-up.
1
2
[2]
(c) Give two different scenarios when a fast broadband connection is essential.
1
2
[2]
(d) How many 4-megabyte files could be downloaded per second using this company’s
broadband?
[1]
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17
14 An expert system has been developed to help diagnose faults in car engines. The software
has been installed on a laptop computer.
For
Examiner's
Use
(a) Describe two desirable features to look for in a laptop rather than a desktop computer.
1
2
[2]
(b) Part of the expert system is supplied on a memory stick. This needs to be plugged into
a USB port for the expert system to work.
Give one reason why this is done.
[1]
(c) Describe two features you would expect to see in the expert system’s interactive user
interface.
1
2
[2]
(d) Apart from the user interface, name three other components that make up a typical
expert system.
1
2
3
[3]
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18
15 A library uses barcodes to identify borrowers and books. A borrower has a card containing
a barcode with an equivalent numerical code. Each book also has a barcode with an
equivalent numerical code.
The flowchart on the facing page shows what happens when book(s) are taken out by a
borrower. However, several stages are missing.
Using item numbers only, complete the flowchart by selecting stages from the item list
below.
Item List
Item
Number
© UCLES 2013
Item Description
1
any more books to scan?
2
has book’s barcode been recognised?
3
has book’s numeric code been recognised?
4
has borrower’s barcode been recognised?
5
has borrower’s numeric code been recognised?
6
input book’s numeric code manually
7
input borrower’s numeric code manually
8
scan in barcode shown in book
9
update borrower and book files
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Examiner's
Use
464
19
For
Examiner's
Use
START
customer selects
book(s)
barcode on
borrower’s
card scanned
No
Yes
Yes
No
OUTPUT
error
message
END
No
No
Yes
Yes
Yes
No
END
[6]
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20
16 (a) A greenhouse is being monitored by a computer using 2 sensors. SENSOR1 measures
the temperature and SENSOR2 measures oxygen levels.
For
Examiner's
Use
If the temperature exceeds 45°C or oxygen levels fall below 0.19, then an error
message is output by the computer.
Write an algorithm, using pseudocode or flowchart only, which
•
•
•
inputs both sensor readings
checks the sensor input values and outputs a warning message if either are out of
range
continues monitoring until the <ESCAPE> key is pressed
(You may assume that READ SENSORn will take a reading from SENSORn and that
READ KEY inputs a key press from the keyboard).
[5]
(b) Describe why a DAC (digital to analogue converter) would be needed if the computer is
used to control the greenhouse environment.
[2]
Permission to reproduce items where third party owned material protected by copyright is included has been sought and cleared where possible. Every
reasonable effort has been made by the publisher (UCLES) to trace copyright holders, but if any items requiring clearance have unwittingly been included, the
publisher will be pleased to make amends at the earliest possible opportunity.
University of Cambridge International Examinations is part of the Cambridge Assessment Group. Cambridge Assessment is the brand name of University of
Cambridge Local Examinations Syndicate (UCLES), which is itself a department of the University of Cambridge.
© UCLES 2013
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CAMBRIDGE INTERNATIONAL EXAMINATIONS
GCE Ordinary Level
MARK SCHEME for the October/November 2013 series
7010 COMPUTER STUDIES
7010/12
Paper 1, maximum raw mark 100
This mark scheme is published as an aid to teachers and candidates, to indicate the requirements of
the examination. It shows the basis on which Examiners were instructed to award marks. It does not
indicate the details of the discussions that took place at an Examiners’ meeting before marking began,
which would have considered the acceptability of alternative answers.
Mark schemes should be read in conjunction with the question paper and the Principal Examiner
Report for Teachers.
Cambridge will not enter into discussions about these mark schemes.
Cambridge is publishing the mark schemes for the October/November 2013 series for most IGCSE,
GCE Advanced Level and Advanced Subsidiary Level components and some Ordinary Level
components.
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Mark Scheme
O Level – October/November 2013
Page 2
Syllabus
7010
Paper
12
(1) (a) For each chosen security issue, 1 mark for description + 1 mark for method of protection.
security issue
hacking
description of security issue
method of protection
gaining illegal/unauthorized
access to a computer system
– use of firewalls
– use of passwords
pharming
code installed on the hard drive of
a user’s computer or on actual
web server; code redirects user to
a bogus/fake website without user
knowing
– use of filters to
authenticate websites
– user should be alert
and look for pharming
clues which indicate
being directed to a
bogus site
phishing
– ISPs can filter/block out
creator sends legitimate-looking
phishing emails
(fake) email in the hope of gaining
– user should be wary of
personal/financial information;
opening links in emails
fake email replicates a well known
company e.g. a bank
spyware
software that gathers information
by monitoring key presses on a
user’s keyboard or activity and
relays the information back to
person who sent the spyware
viruses
Program or coding that replicates
itself /corrupts the system/ alters
or deletes data
– use of dropdown boxes
– user should be alert
and look for clues when
using their computer
– anti-virus (software)
– do not use
disks/software from
unknown sources
– do not open emails
from unknown senders
[6]
© Cambridge International Examinations 2013
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468
Mark Scheme
O Level – October/November 2013
Syllabus
7010
Paper
12
(2) (a) (i) – as first character(s) keyed in, rest of word predicted
/word(s) suggested according to the letter(s) already entered
[1]
(ii) Any two from (items below are only examples):
– MP3 player
– Bluetooth
– wifi
– camera
– Internet surfing
– GPS
[2]
(b) 1 mark for each part:
(i) – less expensive/cheaper than other telephone systems
– can use webcams to have visual as well as text/speech
(ii) – poor quality/drop out/echoes are very common problems
– need to have fast broadband connection to work effectively
(iii) – microphone and speaker/headphones
– headset
[3]
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Mark Scheme
O Level – October/November 2013
Syllabus
7010
Paper
12
(3) (a) 10/ten
(b)
CB, CC,
< - 1 mark - >
[1]
CG, CL
< - 1 mark - >
(–1 mark for each additional item)
[2]
(c) (leather = “Y”) AND (silver = “Y” OR grey = “Y”)
< - 1 mark - > < - - - - - - - - - - 1 mark - - - - - - - - - >
or
(silver = “Y” OR grey = “Y”) AND (leather = “Y”)
< - - - - - - - 1 mark - - - - - - - > < - - - - 1 mark - - - - >
or
(leather = “Y”) AND ((silver = “Y”) OR (grey = “Y”))
< - 1 mark - > < - - - - - - - - - - 1 mark - - - - - - - - - >
or
((silver = “Y”) OR (grey = “Y”)) AND (leather = “Y”)
< - - - - - - - 1 mark - - - - - - - > < - - - - 1 mark - - - - >
[2]
(d) (green = “N”)
[1]
(e) Any one from:
– uses up less memory (NOT space)
– faster to key in data/saves time when keying in data
– fewer mistakes made when keying in data
[1]
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Mark Scheme
O Level – October/November 2013
Syllabus
7010
Paper
12
(4) (a) 1 mark for each application correctly linked to the appropriate hardware items.
speakers
computer
aided design
(CAD)
light pen
microphone
video
conferencing
spaceball
data goggles
virtual reality
webcam
data gloves
[3]
(b) 1 mark for each additional item of hardware
CAD
– 3D (inkjet) printer
– large monitor/screen
– (graph) plotter
– graphics tablet
video conferencing
– broadband modem
– large monitor
virtual reality
– (data) helmet
– simulator headset
– sensor/data suit
– haptic/motion sensor
[3]
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Mark Scheme
O Level – October/November 2013
Page 6
Syllabus
7010
Paper
12
(5)
count
total
a
b
c
d
x
y
temp
1
0
5
4
1
9
18
26
44
44
OUTPUT
34
24
14
4
2
0
5
9
4
1
27
20
47
4
47
37
27
17
7
7
3
< - - - -1 mark - - - >< - - - - - - - - - - 1 mark - - - - - - - - - - ><1 mark><1 mark><1 mark><1 mark>
[6]
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Mark Scheme
O Level – October/November 2013
Syllabus
7010
Paper
12
(6) (a) Any one from:
– circular argument/reference
– value in D2 not yet known
– empty cell D2
(b) = (A2 + C2 * B2)
= (A2 + C2 * 9.81)
(c) = (A7 + C7 * B7)
= (A7 + C7 * 9.81)
[1]
or = (A2 + B2 * C2)
or
or
or
= (A2 + 9.81 * C2)
= (A7 + B7 * C7)
or
[1]
or
= (A7 + 9.81 * C7)
[1]
(d) = MAX(D2:D7)
[1]
(e) = (A2 + B2 * 9.81) or
= (A2 + 9.81 * B2)
[1]
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Mark Scheme
O Level – October/November 2013
Page 8
Syllabus
7010
Paper
12
(7) (a) (i) 1 mark for causes:
– repeated clicking of the mouse
– prolonged use of a keyboard/typing
1 mark for way of removing problem:
– take (regular) breaks
– use wrist supports
– use of ergonomic keyboards
– use of voice recognition software
– adjust chair to correct height
[2]
(ii) Any one from:
– conduits/trunking for wiring
– wires/cables attached to walls
– wires under carpets/floors
– use WiFi connections
[1]
(iii) One mark for risk: e.g.
– glare from/staring for a long period of time at a computer screen
– exposed wires
– inadequate desk support
– sitting too long in the same position
– spilling liquids on computer equipment/inadequate ventilation
One mark for corresponding description of risk (MUST match up)
– can cause headaches/eye strain/dry eye
– risk of electric shock/electrocution
– equipment falling and causing injury
– back/neck pain/injury/strain
– fire risk
[2]
(b) Any two from:
– need for training
– possible redundancies/unemployment
– work patterns may change (e.g. working from home/remote working)
[2]
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Mark Scheme
O Level – October/November 2013
Syllabus
7010
Paper
12
(8) 1 mark for error + 1 mark for suggested correction to error (max of FOUR errors)
description of possible error
suggested correction to error
line 20
lowest = 0
lowest = 100 (or even bigger value)
line 30
loop count is 1 to 100
count should be 1 to 1000
e.g. for count = 1 to 1000
line 50
number = highest
formula is reversed
e.g. should be: highest = number
line 60
number = lowest
formula is reversed
e.g. should be: lowest = number
line 70
count = count + 1
addition of count in a for … to loop
remove line 70 from coding
[8]
(9) Any three from:
– viruses transmitted with attachment
– possible phishing/spyware included with attachment
– attachment file too large/not enough space in mailbox
– she does not have the software to open the file
– attachment corrupted during transmission
– attachment was encrypted (and end user did not have encryption key)
– password needed to open file/attachment (password not known)
– virus checker/firewall detected virus and would not allow file/attachment to be opened
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Mark Scheme
O Level – October/November 2013
Page 10
Syllabus
7010
Paper
12
(10) (a) (i)
A
B
X
0
0
0
1
1
1
1
0
1
1
}
}
1
0
1 mark
1 mark
[2]
(ii) NAND gate
(if truth table above is incorrect, allow follow through in part (ii))
[1]
(b)
A
B
C
X
0
0
0
0
0
1
0
0
0
1
0
0
1
1
1
0
0
1
0
1
1
1
0
1
1
1
0
1
1
1
0
1
}
}
}
}
1 mark
1 mark
1 mark
1 mark
[4]
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Mark Scheme
O Level – October/November 2013
Page 11
Syllabus
7010
Paper
12
(11) (a) 54
[1]
(b) – multiplied by 2
– value 27 is doubled (to become 54)
[1]
(c) 108
[1]
(d) (i)
0
0
1
0
1
1
1
[1]
0
(ii) 184
[1]
(iii) – no more places left in register/binary number
– the left most 1 bit would disappear
– number would become 112 (0111 0000) instead of 368
– number would be greater than 255
– overflow
[1]
(e) – divided by 2
– the number will be halved
[1]
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Mark Scheme
O Level – October/November 2013
Syllabus
7010
Paper
12
(12) (a) Any one from:
– trackerball/touch pad
– touch screen
[1]
(b) Each validation check MUST be different for each input:
goods reference number
– length check
– type/character check
– presence check
– check digit
today’s date
– format check
– presence check
– length check
– range check (on each component)
telephone number
– type/character check
– presence check
– length check
[3]
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Mark Scheme
O Level – October/November 2013
Syllabus
7010
Paper
12
(13) (a) download speed any one from:
– speed at which information/data is transferred FROM server/Internet
– speed at which information/data is transferred TO the user’s computer
upload speed any one from:
– speed at which information/data is transferred FROM user’s computer
– speed at which information/data is transferred TO the Internet/server
[2]
(b) Any two from:
– can use Internet connection and telephone at the same time
– much faster data transfer speed
– always “on”
– charged for number of bytes/flat rate per month rather than actual time on line
– more bandwidth
[2]
(c) Any two from:
– when transferring large files/attachments with emails
– when streaming music/video files/bit streaming
– when using VoIP/video conferencing
– software updates
– online transactions
– Using VLE (Virtual Learning Environment)
[2]
(d) 128 Mbits/sec = 16 Mbytes/sec
Therefore, FOUR (4) files could be downloaded
[1]
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Mark Scheme
O Level – October/November 2013
Syllabus
7010
Paper
12
(14) (a) Any two from:
– lightweight
– long battery life
– cool running processor
– touch pad
– internal webcam
[2]
(b) Any one from:
– security (prevent illegal copying of data)
– storage of additional files/coding required to run software
– software only licensed to specific computers
– to allow the software to run on any computer
[1]
(c) Any two from:
– multiple choice/yes-no answers
– easy to understand interface e.g. use of icons/drop down menus etc.
– output shown as % probabilities of fault
[2]
(d) Any three from:
– knowledge base
– rule(s) base
– inference engine
– explanation system
– (expert system) shell
[3]
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Mark Scheme
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Page 15
15
Syllabus
7010
Paper
12
START
customer selects
book(s)
barcode on
borrower’s
card
No
4
1 mark
1 mark
7
Yes
Yes
5
1 mark
No
OUTPUT
error
message
8
END
No
2
No
3
6
Yes
Yes
1 mark
Yes
1
1 mark
No
9
END
1 mark
[6]
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Mark Scheme
O Level – October/November 2013
Syllabus
7010
Paper
12
(16) (a) marking points:
– correct loop
– reading of BOTH sensors
– check sensor1 + action taken
– check sensor2 + action taken
– read keyboard entry
1 mark
1 mark
1 mark
1 mark
1 mark
sample coding:
repeat
read sensor1
read sensor2
if sensor1 > 45 then print “warning”
if sensor2 < 0.19 then print “warning”
read key
until key = ESCAPE
1 mark
1 mark
1 mark
1 mark
1 mark
[5]
(b) DAC
Any two points from:
– need to convert computer output to analogue values
– to allow it to operate motors, actuators, ……
– …… to open/close windows, switch heaters on/off etc.
– devices may not understand/respond to digital signals
[2]
© Cambridge International Examinations 2013
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UNIVERSITY OF CAMBRIDGE INTERNATIONAL EXAMINATIONS
General Certificate of Education Ordinary Level
*2135265420*
7010/13
COMPUTER STUDIES
October/November 2013
Paper 1
2 hours 30 minutes
Candidates answer on the Question Paper.
No Additional Materials are required.
READ THESE INSTRUCTIONS FIRST
Write your Centre number, candidate number and name on all the work you hand in.
Write in dark blue or black pen.
You may use a soft pencil for any diagrams, graphs or rough working.
Do not use staples, paper clips, highlighters, glue or correction fluid.
DO NOT WRITE IN ANY BARCODES.
Answer all questions.
No marks will be awarded for using brand names of software packages or hardware.
At the end of the examination, fasten all your work securely together.
The number of marks is given in brackets [ ] at the end of each question or part question.
For Examiner's Use
This document consists of 20 printed pages.
IB13 11_7010_13/2RP
© UCLES 2013
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2
1
(a) Name three features of a typical data protection act.
For
Examiner's
Use
1
2
3
[3]
(b) Data being held is often referred to as Personal or Sensitive Personal data.
Give two examples of each type of data.
Personal Data
1
2
Sensitive Personal Data
1
2
[4]
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3
2
(a) The training department of an international airline has introduced computer based
training (CBT) to teach foreign languages to its cabin crew.
For
Examiner's
Use
Give two advantages of using CBT.
1
2
[2]
(b) The airline also trains its pilots.
(i) What type of training is most appropriate to train pilots to manage dangerous
situations?
[1]
(ii) Give two benefits of using this type of training.
1
2
[2]
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4
3
Dmitry’s car is fitted with a Global Positioning System (GPS) navigation system.
For
Examiner's
Use
(a) Explain how the GPS system knows the exact location of Dmitry’s car.
[3]
(b) Dmitry’s GPS system gives out verbal instructions.
(i) Give one benefit and one drawback of doing this.
benefit
drawback
[2]
(ii) Dmitry turns his car onto a main road. His GPS system tells him that he is not on a
road.
Give a possible explanation.
[2]
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5
4
A customer logs on to a bank website so that she can access her account.
(a) The first thing she was asked to do was to give the 3rd, 4th and 7th character of her
password. This was done using drop-down boxes:
For
Examiner's
Use
Give two reasons why the customer was asked to supply only 3 characters from her
password.
1
2
[2]
(b) Authentication is a technique used in bank security to check that the customer is who
they say they are. This involves three pieces of information, other than the password,
all related to the customer.
Give three examples of suitable information:
1
2
3
[3]
© UCLES 2013
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6
5
A website has been set up allowing users to access the Periodic Table. Part of the table is
shown below.
He
H
Li Be
B
C
N
O
F Ne
Na Mg
Al Si
P
S
Cl Ar
K Ca Sc Ti
V Cr Mn Fe Co Ni Cu Zn Ga Ge As Se Br Kr
A user selects an element from the table and is then directed to another web page where
details of the chosen element can be found.
(a) (i) What would be the most suitable input device for this application?
[1]
(ii) Describe how your chosen input device would interact with the table.
[1]
(b) Give two advantages of this system when compared to finding the same information
from books.
1
2
[2]
(c) Apart from security issues, give two disadvantages of this system compared to using
books.
1
2
[2]
© UCLES 2013
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For
Examiner's
Use
488
7
6
Patients in a hospital are monitored for vital signs (for example, heart beat and
temperature) by sensors and a computer system. Results are displayed on a monitor in the
form of numbers and graphs.
For
Examiner's
Use
(a) Describe how the sensors and computer system are used to monitor the patients and
to alert doctors and nurses of a possible problem.
[3]
(b) Give two advantages of using this system rather than 24 hour monitoring by nurses.
1
2
[2]
(c) Why is the output shown in both graphical and numerical form?
[2]
© UCLES 2013
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8
7
(a) Describe what is meant by streaming when watching a video on a computer screen.
For
Examiner's
Use
[2]
(b) What is the difference between true (real time) streaming and on demand streaming?
true
on demand
[2]
(c) To allow high quality video playback during streaming, computers need special
software and a way of temporarily saving the data.
Describe one piece of software needed and also how the data can be stored
temporarily.
software
temporary storage
[2]
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9
(d) Give one benefit and one drawback of using streaming to play videos.
For
Examiner's
Use
benefit
drawback
[2]
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10
8
A company decides to offer a computer aided design (CAD) service.
(a) Give two advantages and two disadvantages to the designer of using CAD rather than
using manual, paper-based systems.
Advantages:
1
2
Disadvantages:
1
2
[4]
(b) The company sets up call centres overseas to help give customers advice.
(i) Give two benefits to the company.
1
2
[2]
(ii) Give two drawbacks to the company.
1
2
[2]
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Examiner's
Use
492
11
9
A database was set up to keep track of goods in a shop. A section of the database is shown
below.
Item
code
1113
1124
1200
1422
1515
1668
1801
1844
Number in
stock
155
84
30
600
90
58
60
195
Re-order
level
200
50
60
500
100
50
100
200
Price of
item ($)
1.50
2.50
5.00
1.00
2.00
4.00
8.00
1.50
Value of
stock ($)
232.50
210.00
150.00
600.00
180.00
232.00
480.00
292.50
For
Examiner's
Use
Items
ordered
Yes
No
Yes
No
No
No
No
Yes
(a) How many records are shown in this section of database?
[1]
(b) (i) Using Item code only, what would be output if the following search was carried
out:
(Number in stock < Re-order level) AND (Items ordered = “No”)
[2]
(ii) What useful information does this search produce?
[1]
(c) Write a search condition to locate items costing more than $2.00 or have a stock value
exceeding $300.00.
[2]
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12
10 (a) The following pseudocode was written to input 1000 dates.
1
2
3
4
5
For
Examiner's
Use
count = 1
repeat
input day, month, year
count = count + 1
until count = 1000
(i) Describe why the loop only inputs 999 dates instead of 1000.
[1]
(ii) What needs to be changed or added to the above code to make sure 1000 dates
are input?
[1]
(b) Errors in code can be found using test data.
Name three different types of test data. Using month from the pseudocode above, give
an example of each type of test data.
test data type 1
example
test data type 2
example
test data type 3
example
[6]
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13
11 (a) Draw the logic circuit for the following logic statement:
For
Examiner's
Use
X = 1 if [ A is NOT 1 AND B is 1 ] AND [ B is 1 OR C is 1 ]
A
B
X
C
[4]
(b) Complete the truth table for the above logic circuit.
Working space
A
B
C
0
0
0
0
0
1
0
1
0
0
1
1
1
0
0
1
0
1
1
1
0
1
1
1
X
[4]
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14
12 A spreadsheet was set up to compare fuel prices in dollars per litre over three years. Part
of the spreadsheet is shown below.
A
1
2
3
4
5
6
7
8
9
10
country 1
country 2
country 3
country 4
country 5
country 6
country 7
country 8
B
C
D
E
F
Year 1
($/litre)
Year 2
($/litre)
Year 3
($/litre)
Average
($/litre)
Above world
average in
year 3?
2.00
2.50
2.00
1.00
2.00
2.20
2.15
1.50
2.40
2.70
2.10
1.25
2.20
2.80
2.45
1.70
Max value:
2.75
2.90
2.30
1.40
2.50
3.00
2.80
2.00
3.00
2.38
2.70
2.13
1.22
2.23
2.67
2.47
1.73
(a) What formulas must be in column E to calculate the average values for years 1 to 3?
E
Average
($/litre)
1
2
=
3
=
4
=
5
=
6
=
7
=
8
=
9
=
[2]
(b) What formula must be in cell D10 to find the highest fuel value in $/litre for year 3?
=
[1]
(c) (i) If the following formula was typed into cell F2, what would be output?
= IF (D2 > 2.20, “Y”, “N”)
[1]
© UCLES 2013
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For
Examiner's
Use
496
15
(ii) If the formula from part (c)(i) was replicated all the way down to F9, what values
would be shown in cells F2 to F9?
For
Examiner's
Use
F
1
Above world
average in
year 3?
2
3
4
5
6
7
8
9
[2]
(d) (i) If the following formula was typed into cell E10, what would be output?
= COUNTIF (E2:E9, “> 2.20”)
[1]
(ii) What formula would need to be in cell F10 to count the number of “Y” entries in
column F?
=
© UCLES 2013
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16
13 A touch screen is divided up into a number of locations:
For
Examiner's
Use
x values
0
1
2 ......................................................... 61 62 63
0
1
2
.......................
y values
30
31
Each x-position is shown in a 6-bit register:
32
16
8
4
2
1
and each y-position is shown in a 5-bit register:
16
8
4
2
1
Thus,
32
16
8
4
2
1
16
8
4
2
1
0
1
1
1
1
0
1
0
1
0
1
refers to screen position:
(30, 21)
(a) Give the screen position referred to if the two registers contain:
32
16
8
4
2
1
16
8
4
2
1
1
1
0
1
0
0
0
1
1
1
0
(
© UCLES 2013
,
)
[2]
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17
(b) Three options (A, B, C) are shown on the touch screen below:
position
(20, 11)
A
C
position
(40, 11)
For
Examiner's
Use
B
position
(30, 25)
If the two registers contain:
32
16
8
4
2
1
16
8
4
2
1
1
0
1
0
0
0
0
1
0
1
1
what option (A, B or C) has been chosen?
[1]
(c) Each box A, B, C is made up of 128 x 64 pixels.
(i) What is meant by the term pixel?
[1]
(ii) The value of each pixel is stored in 1 byte of memory.
How much memory is needed to store one of these boxes?
Give your answer in kilobytes.
[2]
© UCLES 2013
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18
14 A microprocessor controls the opening and closing of automatic doors to a supermarket.
Customers are detected using pressure sensors.
The flowchart on the next page shows how the sensors and microprocessor interact to
control the opening and closing of the doors. However, several of the stages in the process
have been missed out.
Using item number only, complete the flowchart using items from the following list:
Item
number
© UCLES 2013
Item description
1
ADC changes analogue signal into
digital signal
2
are the doors already open?
3
DAC changes digital signal into
analogue signal
4
DAC changes digital signal into
analogue signal
5
doors are closed
6
microprocessor sends signal
7
microprocessor sends signal
8
no action is required
9
wait for 10 seconds
7010/13/O/N/13
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Examiner's
Use
500
19
For
Examiner's
Use
START
No
has sensor
detected a
customer?
Yes
Yes
No
doors are
opened
Yes
has sensor
detected a
customer?
No
[5]
© UCLES 2013
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20
15 5000 numbers are being input which should have either 1 digit (e.g. 5), 2 digits (e.g. 36), 3
digits (e.g. 149) or 4 digits (e.g. 8567).
For
Examiner's
Use
Write an algorithm, using pseudocode or flowchart only, which
•
•
•
inputs 5000 numbers
outputs how many numbers had 1 digit, 2 digits, 3 digits and 4 digits
outputs the % of numbers input which were outside the range
[6]
Permission to reproduce items where third party owned material protected by copyright is included has been sought and cleared where possible. Every
reasonable effort has been made by the publisher (UCLES) to trace copyright holders, but if any items requiring clearance have unwittingly been included, the
publisher will be pleased to make amends at the earliest possible opportunity.
University of Cambridge International Examinations is part of the Cambridge Assessment Group. Cambridge Assessment is the brand name of University of
Cambridge Local Examinations Syndicate (UCLES), which is itself a department of the University of Cambridge.
© UCLES 2013
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CAMBRIDGE INTERNATIONAL EXAMINATIONS
GCE O Level
MARK SCHEME for the October/November 2013 series
7010 COMPUTER STUDIES
7010/13
Paper 1; maximum raw mark 100
This mark scheme is published as an aid to teachers and candidates, to indicate the requirements of
the examination. It shows the basis on which Examiners were instructed to award marks. It does not
indicate the details of the discussions that took place at an Examiners’ meeting before marking began,
which would have considered the acceptability of alternative answers.
Mark schemes should be read in conjunction with the question paper and the Principal Examiner
Report for Teachers.
Cambridge will not enter into discussions about these mark schemes.
Cambridge is publishing the mark schemes for the October/November 2013 series for most IGCSE,
GCE Advanced Level and Advanced Subsidiary Level components and some Ordinary Level
components.
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Page 2
1
Syllabus
7010
Paper
13
(a) Any three from:
–
–
–
–
–
–
–
–
–
data should be obtained/processed fairly/lawfully
data should be obtained only for one or more specified purposes
data should be adequate/relevant/not excessive (in relation to its purpose)
data should be accurate/up to date
data should be held no longer than necessary (for the purpose for which it was obtained)
data should be processed in accordance with the rights of the data subjects
data should be kept securely/safely (with adequate levels of protection)
data should only be transferred to countries with an adequate level of protection (safe
harbour)
data subjects have the right to see data about them and/or have it altered/removed if
incorrect
[3]
(b) Personal data: any two from:
e.g.
– name (surname and/or forename)
– address
– telephone/mobile number
– passport/id number
– date of birth
– email address
Sensitive personal data: any two from:
e.g.
– racial/ethnic origin
– political opinions
– religious beliefs
– Trades Union membership
– physical/mental health
– sexual life/orientation
– criminal convictions
2
[4]
(a) Any two from:
–
–
–
–
–
–
–
user can work at their own speed
user can learn in their own time/when/where they want
user can re-run sections of training package whenever they wish
user can pause the training at any point
user gets immediate feedback/analysis (on their performance)
there is no need to have teachers or classrooms
less expensive for the airline/ training department
[2]
(b) (i) flight simulator/simulating/simulation
[1]
(ii) Any two from:
–
–
–
–
–
can be much safer
less expensive than building/crashing the real thing
repetition of scenarios (e.g. potential crashes)
different scenarios/situations available
no need for an instructor
[2]
© Cambridge International Examinations 2013
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Mark Scheme
GCE O Level – October/November 2013
Page 3
3
Syllabus
7010
Paper
13
(a) Any three from:
–
–
–
–
–
–
–
–
satellites transmit signals (to the GPS in the car)
the computer receives/interprets these signals
the system depends on very accurate timing/atomic clocks
each satellite transmits its location and time
computer in the vehicle calculates its position based on at least 3 satellite signals
system makes use of triangulation (to pinpoint its exact location)
position of vehicle accurate to within 1 metre
at least 24 satellites in operation
(b) (i)
[3]
benefits (any one from)
–
–
–
safer because e.g. driver can keep their eyes on the road
verbal instructions can be easier/quicker to understand by driver
a comparative safety issue
drawbacks (any one from)
–
–
–
(ii)
[2]
Any two from:
–
–
–
–
4
can be distracting to the driver
may not hear instructions (clearly)
inappropriate words
maps in GPS (sat nav) may be out of date/new road
position of the car is in error
fault in software in device
interference/loss of signal e.g. due to weather
[2]
(a) Any two from:
– hackers only get part of the password
– can ask for different characters/combinations each time
– helps to “defeat” spyware
[2]
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Mark Scheme
GCE O Level – October/November 2013
Page 4
Syllabus
7010
Paper
13
(b) Any three from:
customer knows:
e.g.
– PIN
– Name/user name
– date last logged on
– memorable word/phrase/graphic
– memorable personal data e.g. mother’s maiden name
– date of birth
– email address
– recent activities
– telephone number
– customer number
– account number
belongs to customer:
–
bank card (number)
unique to customer:
–
5
biometrics (e.g. fingerprints)
[3]
(a) (i) Any one from:
–
–
–
touch screen
mouse/trackerball/touch pad
keyboard
[1]
(ii) Any one from:
–
–
–
touch required element on screen with finger (and go to relevant web page)
pointer moved and element selected (mouse/trackerball/touch pad)
use arrow keys on keyboard to select required element and then press [ENTER] key
OR key characters and press [ENTER]
[1]
(b) Any two from:
–
–
–
–
–
–
much faster/easier to access information
more up to date (since easier to modify than books)
more convenient than carrying around many text books
many people can access the data at the same time
using multi-media (possible to improve learning environment)
easier to import information into an “essay” (for example)
[2]
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Mark Scheme
GCE O Level – October/November 2013
Page 5
(c)
Paper
13
Any two from:
–
–
–
–
–
–
6
Syllabus
7010
Accuracy issues e.g. anyone can write a web page, information is limited to author’s knowledge
health and safety risks from prolonged use of computer
risk of finding undesirable web sites
possibility of information overload when doing searches
Internet access required
Power source required
[2]
(a) Any three from:
–
–
–
–
–
–
–
sensors for oxygen, heart/pulse rate (etc.) send signals to computer
converted (by ADC) into digital data
computer compares this data with stored data/pre-set values
sends vital signs data to monitors
if the new information is out of range, computer sends signals
to sound an alarm/warn doctors and nurses
signals need to be first converted into analogue (by DAC)
monitoring is continuous (until machine is switched off)
[3]
(b) Any two from:
–
–
–
–
nurse issues e.g. nurses get tired, need breaks
can show immediate trends (automatically)
faster response to a given set of conditions
less expensive because e.g. leaves nurses free to do other tasks while computer
monitors patients, less wages
[2]
(c) Any two from:
–
–
–
–
7
easier to see immediate trends in data using a graph
“OK” graph and “not OK” graph may be easier to recognise at a glance
numbers are easier to read in some cases (e.g. temperature)
no need to interpret/understand numbers
[2]
(a) Any two from:
–
–
–
–
data sent in a compressed form
over the Internet
displayed to user in real time
makes use of buffering
[2]
(b) true (any one from)
–
–
–
information sent straight to user’s computer
no need to save information first on servers’ hard disk
data is live (in real time)
on demand (any one from)
–
–
files saved on servers’ hard disk first
then played back to user as required
[2]
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Mark Scheme
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Page 6
Syllabus
7010
Paper
13
(c) software (any one from)
–
–
–
media player
decompression software
CODEC
temporary storage
–
use of buffers
[2]
(d) benefit (any one from)
–
–
–
no need to store the files/saves on memory space
can be sent directly to any receiving device
available anytime
drawback (any one from)
–
–
–
8
slow due to e.g. buffering, broadband speed
video “gaps”/jumps as data is streamed
video withdrawn
[2]
(a) Advantages (any two from)
–
–
–
–
–
–
–
–
easier to modify the drawings
can keep a “library of parts”
special features available e.g. zoom, rotation
can do automatic costings
easier to create a model from the design
easier to do ergonomic studies on new designs
can automatically carry out stress/loading calculations
direct link into CAM is possible
Disadvantages (any two from)
–
–
possible need for training
higher costs e.g. start-up, on-going
(b) (i)
[4]
benefits (any two from)
–
–
–
–
(ii)
reduced costs in countries where labour costs are lower
reduced costs in countries where incentives are given to set up companies
round the clock (24/7) customer support is possible
if workers on strike in one country, can move work somewhere else
[2]
drawbacks (any two from)
–
–
–
–
–
language and culture problems can make it difficult for company
possible negativity to overseas call centres (loss of customers)
need for (expensive) training programmes
start-up costs
possible unreliability of infrastructure
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508
Mark Scheme
GCE O Level – October/November 2013
Page 7
9
Syllabus
7010
Paper
13
(a) 8
[1]
(b) (i) 1515
1801
(–1 mark for each error)
[2]
(ii) –
–
checks whether new goods have (yet) to be ordered
to maintain stock levels
(c) (Price of item ($) > 2)
< - - - - 1 mark - - - - >
or
OR
[1]
(Value of stock ($) > 300)
< - - - - - - - - - 1mark - - - - - - - - >
(Value of stock ($) > 300)
OR
(Price of item ($) > 2)
< - - - - - - 1 mark - - - - - -> < - - - - - - - 1mark - - - - - - >
10 (a) (i) –
–
(ii) –
–
–
(b) –
[2]
value of count starts at 1 so only 999 iterations
value of count reaches 1000, but before 1000th input
line 1 should read count = 0
line 5 should read count = 1001 (or count >1000)
change to appropriate loop structure
[2]
1 mark for naming data type + 1 mark for example related to month
–
–
normal/valid (test data)
any value in given range (1 to 12) e.g. 4
–
–
–
abnormal/invalid (test data)
any value which is outside the range/any value not acceptable
i.e. letters, negative numbers, values > 12 e.g. adfrk, -20, 36
–
–
–
extreme/boundary (test data)
data which is on the boundaries/edges of the acceptable range
i.e. 1 or 12 for extreme; 0, 1, 12 or 13 for boundary
–
Month names, instead of values, are acceptable e.g. April
[6]
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Mark Scheme
GCE O Level – October/November 2013
Syllabus
7010
Paper
13
11 (a)
(1 mark for EACH correct logic gate)
[4]
© Cambridge International Examinations 2013
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Page 9
Syllabus
7010
Paper
13
(b)
A
B
C
X
0
0
0
0
0
0
1
0
0
1
0
1
0
1
1
1
1
0
0
0
1
0
1
0
1
1
0
0
1
1
1
0
}
}
}
}
1 mark
1 mark
1 mark
1 mark
[4]
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Mark Scheme
GCE O Level – October/November 2013
12 (a)
1
2
3
4
5
6
7
8
9
Syllabus
7010
Paper
13
E
Average
($/litre)
= AVERAGE (B2:D2)
–1 for each
error
= AVERAGE (B3:D3)
Working
equivalents
acceptable
= AVERAGE (B4:D4)
= AVERAGE (B5:D5)
Allow follow
through
= AVERAGE (B6:D6)
= AVERAGE (B7:D7)
= AVERAGE (B8:D8)
= AVERAGE (B9:D9)
[2]
(b) MAX (D2:D9)
[1]
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Mark Scheme
GCE O Level – October/November 2013
Page 11
(c) (i)
Syllabus
7010
Paper
13
Y or “Y”
[1]
(ii)
1
F
Above world average in
year 3?
Y
2
Y
1 mark
3
Y
4
N
5
Y
6
Y
7
Y
1 mark
8
N
9
[2]
(d) (i)
5
[1]
(ii) = COUNTIF (F2:F9, “Y”)
13 (a) (52,
1 mk
[1]
14)
1 mk
[2]
(b) B
(c) (i) –
–
[1]
smallest element that makes up a picture
short for picture element
(ii) 128 × 64
[1]
= 8192 bytes of memory
= 8 kilobytes
(2 marks for correct answer, 1 mark for good attempt at calculation)
[2]
© Cambridge International Examinations 2013
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Mark Scheme
GCE O Level – October/November 2013
Syllabus
7010
Paper
13
14
START
No
has sensor
detected a
customer?
Yes
1 mark
1 mark
1
Yes
2
8
No
1 mark
6/7
3/4
doors are
opened
9
1 mark
Yes
has sensor
detected a
customer?
No
7/6
1 mark
4/3
5
[5]
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Mark Scheme
GCE O Level – October/November 2013
Page 13
Syllabus
7010
Paper
13
15 marking points:
–
–
–
–
–
–
–
–
initialisation
correct loop structure (1 to 5000)
input numbers (INSIDE a loop)
test for how many digits in all input numbers
increment all relevant totals
increment error total as appropriate
calculate % errors in input numbers
output ALL four totals + percent value (OUTSIDE a loop)
1 mark
1 mark
1 mark
1 mark
1 mark
1 mark
1 mark
1 mark
sample coding:
single = 0: two = 0: three = 0: four = 0: error = 0
1 mark
for x = 1 to 5000
1 mark
input number
1 mark
if number > 999 and number < 10000 then four = four + 1 }
else if number > 99 then three = three + 1
}
2
else if number > 9 then two = two + 1
}
marks
else if number > 0 then single = single + 1
else error = error + 1
}
1 mark
next x
percent = error/50
1 mark
print single, two, three, four, percent
1 mark
[6]
© Cambridge International Examinations 2013
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Cambridge International Examinations
Cambridge Ordinary Level
*1459661344*
COMPUTER STUDIES
7010/11
May/June 2014
Paper 1
2 hours 30 minutes
Candidates answer on the Question Paper.
No Additional Materials are required.
READ THESE INSTRUCTIONS FIRST
Write your Centre number, candidate number and name on all the work you hand in.
Write in dark blue or black pen.
You may use an HB pencil for any diagrams, graphs or rough working.
Do not use staples, paper clips, glue or correction fluid.
DO NOT WRITE IN ANY BARCODES.
Answer all questions.
No marks will be awarded for using brand names of software packages or hardware.
At the end of the examination, fasten all your work securely together.
The number of marks is given in brackets [ ] at the end of each question or part question.
The maximum number of marks is 100.
This document consists of 20 printed pages.
IB14 06_7010_11/FP
© UCLES 2014
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2
1
(a) Name and draw two types of network topology.
Name 1
Drawing 1
Name 2
Drawing 2
[4]
(b) Give two benefits of having computers networked together.
1
2
[2]
(c) Give one drawback of having computers networked together.
[1]
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3
2
(a) (i) A student wrote: “batch processing can be used when making airline bookings”.
Why is this statement incorrect?
[1]
(ii) The same student also wrote: “to launch an application, a graphical user interface (GUI)
requires typing the name of the application using a keyboard”.
Why is this statement incorrect?
[1]
(b) A user interface is a function of a typical operating system.
Write down four other functions of a typical operating system.
1
2
3
4
[4]
© UCLES 2014
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4
3
A hospital holds records of its patients in a database. Four of the fields are:
•
•
•
•
date of visit (dd/mm/yyyy)
patient’s height (m)
8-digit patient ID
contact telephone number
The presence check is one possible type of validation check on the data. For each field, give
another validation check that can be performed. Give an example of data which would fail your
named validation check.
A different validation check needs to be given for each field.
field name
name of validation check
example of data which would
fail the validation check
date of visit
patient’s height
patient ID
contact
telephone
number
[8]
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5
4
The diagram below shows a number of descriptions and terms used in computer security.
By drawing arrows, connect the correct description to the computer security term.
Program installed on a PC to
gather data about the user. It
monitors every key press and
relays the data back to the home
base.
Cookies
Junk (unsolicited) electronic mail
advertising products and services
sent to a general mailing list.
Phishing
Sending an email that claims to be
from a legitimate company; the
recipient is then directed to a bogus
website where their personal
details will be collected.
Pharming
Malicious code installed on a PC or
on a server. This code directs
users to a fraudulent website
without their knowledge.
Spyware
Act of locating and possibly
exploiting a wireless network by
touring an area. This requires a
laptop with relevant software and
an antenna.
Spam
Information that a website stores
about a user on the user’s hard
disk; this enables the website to
remember details about the user
when they next visit the website.
War-driving
[5]
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6
5
A floor turtle can use the following instructions.
Instruction
Meaning
FORWARD x
Move x cm forwards
BACKWARD x
Move x cm backwards
LEFT t
Turn left t degrees
RIGHT t
Turn right t degrees
REPEAT n
Repeat next set of instructions n times
ENDREPEAT
Finish repeated instructions
PENUP
Lift the pen
PENDOWN
Lower the pen
Each square is
10 cm by 10 cm
Each diagonal
line is 28 cm long
cm
28
© UCLES 2014
45°
45°
Start
Finish
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7
Complete the following set of instructions to draw the shape in the direction shown by the arrows.
PENDOWN
7
LEFT 45
8
1
9
2
10
3
11
4
12
5
13
6
14
[5]
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8
6
A company has eight warehouses throughout Europe. It has decided to introduce online sales
and has launched a website.
Customers can now buy online instead of physically going to the warehouse.
(a) Give two benefits to the customer.
1
2
[2]
(b) Give two benefits to the company.
1
2
[2]
(c) Give three potential effects on the staff who presently work for the company.
1
2
3
[3]
(d) Give two features you would expect to see on the company’s website.
1
2
[2]
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9
7
(a) Draw the logic circuit for the logic statement:
X = 1 if (L is NOT 1 AND F = 1) OR (F is NOT 1 AND A is 1)
L
F
X
A
[5]
(b) Complete the truth table for the above system.
Working space
L
F
A
0
0
0
0
0
1
0
1
0
0
1
1
1
0
0
1
0
1
1
1
0
1
1
1
X
[4]
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10
8
Study the following flowchart very carefully.
START
INPUT number
product = 1
value = number
product = value * product
value = value – 1
No
is value = 0?
Yes
OUTPUT number, product
STOP
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11
Complete the trace table for the input value of 5:
number
product
value
OUTPUT
[4]
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12
9
A spreadsheet has been set up to monitor six experiments.
A
1
2
3
4
5
6
7
8
B
Start
volume
(litres)
21
19
20
18
20
19
Experiment
number
1
2
3
4
5
6
C
End
volume
(litres)
33
40
37
48
44
33
D
Volume
change
(litres)
12
21
17
30
24
14
E
F
G
Start
End
Pressure
pressure pressure change
(bar)
(bar)
(bar)
1.0
2.2
1.2
1.0
3.3
2.3
1.0
3.0
2.0
1.0
3.6
2.6
1.0
3.4
2.4
1.0
2.6
1.6
(a) What formulas must be in column D and column G?
1
D
G
Volume change
(litres)
Pressure change
(bar)
2 =
=
3 =
=
4 =
=
5 =
=
6 =
=
7 =
=
[4]
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13
(b) What cells were highlighted to draw the chart below?
3
Chart to show volume and pressure change
50
2.5
40
2
30
1.5
20
1
10
0.5
0
Pressure
Volume
60
0
1
2
3
4
Experiment number
5
6
[2]
(c) What formula should be in cell D8 to find the average volume change?
=
[1]
(d) What formula should be in cell G8 to find the highest pressure change?
=
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14
10 You have been asked to write a report on the use of the following communication methods:
•
•
•
mobile phones
video conferencing
emails
Describe a benefit and a drawback of each of the above communication methods.
mobile phones
Benefit
Drawback
video conferencing
Benefit
Drawback
emails
Benefit
Drawback
[6]
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15
11 Dima has decided to change his dial-up modem for a broadband modem.
(a) Give two advantages of doing this.
1
2
[2]
(b) Dima has agreed to send Michaela a 20 megabyte file. They both have a broadband
connection.
Dima has to upload his file to a server and then Michaela needs to download it from the
same server.
The broadband data transfer rates (speeds) are:
1 megabits per second to upload a file
8 megabits per second to download a file
(Note: 8 bits = 1 byte)
(i) How long does it take to upload Dima’s file?
[2]
(ii) How long does it take to download Dima’s file?
[1]
(c) Dima has decided to use wireless LAN (WiFi) connections.
Give one advantage and one disadvantage of doing this.
Advantage
Disadvantage
[2]
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16
12 A digital light meter has a 3-digit LCD. The value of each digit on the instrument display is stored
as a 4-bit binary number in a register.
For example:
X
Y
8
4
2
1
0
1
1
1
X
0
1
0
0
Y
0
1
0
1
Z
Z
is represented by:
(a) What value is shown on the display if the 4-bit binary registers contain:
X
8
4
2
1
0
0
1
0
X
Y
1
0
0
1
Z
0
0
0
1
Y
Z
[3]
(b) What would be stored in the 4-bit binary registers if the display shows:
8
4
2
1
X
X
Y
Z
Y
Z
[3]
(c) If any of the 4-bit binary registers X, Y or Z contain the value 1 1 1 1 this indicates an error.
(i) How could this error be shown on the instrument display?
[1]
(ii) What could cause an error to occur?
[1]
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17
13 A heating system is being controlled by sensors and a computer. The temperature must be kept
between 15°C and 25°C. If 30°C is exceeded a warning message is generated and the system
shuts down.
A flowchart of the process is shown below. Some of the items are missing.
Complete the flowchart, using item number only, from the list of items given.
START
LIST OF ITEMS
Item
Number
READ data from
temperature
sensors
Item
Description
1
convert data to digital using ADC
2
are data digital?
3
is temperature < 15 °C?
4
is temperature > 25 °C?
5
is temperature > 30 °C?
6
output warning message
7
send signal to turn OFF the heater
8
send signal to turn the heater ON
9
send signal to shut down the heater
No
Yes
Yes
No
STOP
Yes
No
No
Yes
[4]
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18
14 A database was set up showing statistics for some states in the USA. Part of the database is
shown below.
Ref
Name of
state
Population
(millions)
Number
of houses
(millions)
Area
(sq miles)
Density
Travel
time
to work
(min)
OR
CO
NJ
TX
CA
FL
AK
NV
NY
Oregon
Colorado
New Jersey
Texas
California
Florida
Alaska
Nevada
New York
3.8
4.9
8.7
24.3
36.8
18.3
0.7
2.6
19.5
1.6
2.1
3.5
9.4
13.3
8.7
0.3
1.1
7.9
96 000
104 000
7 400
262 000
156 000
53 900
572 000
110 000
47 000
39.6
47.1
1175.7
92.7
235.9
339.5
1.2
23.6
414.9
22.3
24.3
30.0
25.4
27.7
26.2
19.6
23.3
31.7
(a) (i) How many records are in this section of the database?
[1]
(ii) How many fields are in each record?
[1]
(b) The following search condition was entered:
(Population (millions) < 4.0) OR (Number of houses (millions) < 4.0)
Using Ref only, write down which records will be found.
[2]
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19
(c) Write down the search condition to find out which states have an area over 100 000 square
miles and where it takes less than 25 minutes to get to work.
[2]
(d) (i) What should be the key field in this database?
[1]
(ii) Give a reason for your choice.
[1]
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20
15 A survey is being carried out which involves reading and recording sound levels near a busy road
junction. Once all the data are collected, they are input manually into a computer. A sound level
of 0 decibels (0 dB) is input to indicate the end of the data.
Write an algorithm, using pseudocode or a flowchart, which:
•
•
inputs all the sound levels
after a sound level of 0 is input, outputs the following:
o average sound level
o highest recorded sound level.
[6]
Permission to reproduce items where third party owned material protected by copyright is included has been sought and cleared where possible. Every
reasonable effort has been made by the publisher (UCLES) to trace copyright holders, but if any items requiring clearance have unwittingly been included, the
publisher will be pleased to make amends at the earliest possible opportunity.
Cambridge International Examinations is part of the Cambridge Assessment Group. Cambridge Assessment is the brand name of University of Cambridge Local
Examinations Syndicate (UCLES), which is itself a department of the University of Cambridge.
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CAMBRIDGE INTERNATIONAL EXAMINATIONS
GCE Ordinary Level
MARK SCHEME for the May/June 2014 series
7010 COMPUTER STUDIES
7010/11
Paper 1, maximum raw mark 100
This mark scheme is published as an aid to teachers and candidates, to indicate the requirements of
the examination. It shows the basis on which Examiners were instructed to award marks. It does not
indicate the details of the discussions that took place at an Examiners’ meeting before marking began,
which would have considered the acceptability of alternative answers.
Mark schemes should be read in conjunction with the question paper and the Principal Examiner
Report for Teachers.
Cambridge will not enter into discussions about these mark schemes.
Cambridge is publishing the mark schemes for the May/June 2014 series for most IGCSE, GCE
Advanced Level and Advanced Subsidiary Level components and some Ordinary Level components.
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Mark Scheme
GCE O LEVEL – May/June 2014
Syllabus
7010
Paper
11
(a) 1 mark for correct name + 1 mark for correct corresponding diagram.
ring
star
bus
[4]
(b) Any two from:
– shared resources
– better/easier communications
– easier to “keep track” of users from a central point
– all computers/users can share same data/programs (stored on a central
database)/easier transfer of data between computers
– can access your files from any computer on the network
[2]
(c) Any one from:
– greater risk of spreading viruses to other computers/the network
– increased security risks when computers connected together
– failure of server affects all stations
[1]
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537
Mark Scheme
GCE O LEVEL – May/June 2014
Syllabus
7010
Paper
11
(a) (i) Any one from:
– airline bookings need to be done in real time to stop double bookings
– batch processing only done at the end of the day/week so double booking is possible
[1]
(ii) Any one from:
– GUI uses pointing devices/icons/windows (mouse, trackerball, ……)
– keyboard used with command line interfaces
(b) Any four functions from:
– file management/delete/copy/save/store/load files
– controls/manages software/hardware
– memory management
– I/O control
– error messages/handling
– security issues
– logging on/off
– accounting/user account management
– time slicing
– multi access
– multi tasking/task management
– JCL/job control/batch processing
– network management
3
[1]
[4]
1 mark for naming validation check + 1 mark for correct matching example
field name
name of validation check
example of data which
would fail validation check
date of visit
format check
e.g. 2012/12/04
e.g. 3rd March 2012
patient’s height
type/character check
range check
limit check
can’t be < 0 or > 2.5m
e.g. –5, five
e.g. 8, -3,
patient ID
type check
length check
range check
(can’t be < 0 or > 99999999)
e.g. 3142ABCD
e.g. 2131451, 136498207
e.g. –3, 851341625
contact telephone
number
e.g. 0773141621834
e.g. 7H215GD
e.g. 01223/123456/8901234
length check
type/character check
format check
[8]
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538
Mark Scheme
GCE O LEVEL – May/June 2014
Syllabus
7010
Paper
11
1 mark for each correct arrow up to the maximum of 5 marks.
Program installed on a PC to gather
information about the user. It monitors
every key press and relays the
information back to the home base.
Cookies
Junk/ (unsolicited) electronic mail
advertising products and services sent
to a general mailing list.
Phishing
Sending an email that claims to be from
a legitimate company; the recipient is
then directed to a bogus website where
their personal details will be collected.
Pharming
Malicious code installed on a PC or on
a server. This code directs users to a
fraudulent website without their
knowledge.
Spyware
Act of locating and possibly exploiting a
wireless network by touring an area.
This requires a laptop with relevant
software and an antenna.
Spam
Information that a website stores about
a user on their hard disk; this enables
the website to remember details about
the user when they next visit the
website.
War-driving
[5]
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539
Mark Scheme
GCE O LEVEL – May/June 2014
Syllabus
7010
Paper
11
pendown
left 45
-----------forward 28
right 45
-----------forward 20
right 135
-----------forward 28
left 90
-----------forward 28
right 135
-----------forward 20
right 45
forward 28
-----------(penup)
(left 45)
(1 mark)
(1 mark)
(1 mark)
(1 mark)
(1 mark)
[5]
6
(a) Any two from:
– any reference to cost saving plus reason
– any reference to time saving plus reason
– possible to order 24/7
– goods delivered to customer’s house (may be heavy/large goods)
– customers who don’t live in Europe can buy goods
[2]
(b) Any two from:
– use of cookies (to find customer preferences)
– open 24/7
– wider customer base (potentially)
[2]
(c) Any three from:
– possible redundancies
– need to re-train/learn new skills/job role within company can change
– possibility of working from home
– relocation of certain staff (to a different warehouse)
– increased health risk to staff due to more computer-based work
[3]
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Mark Scheme
GCE O LEVEL – May/June 2014
Page 6
Syllabus
7010
Paper
11
(d) Any two from:
– secure payment method
– shopping basket
– checkout
– search facility
– “remember customer”/log in
– customers who bought “X” also bought “Y” facility
– hyperlinks to other pages/websites
– currency converter
– create customer account
– description of the products for sale
– contact details
7
[2]
(a) 1 mark per correct logic gate (accept other gate symbols)
[5]
(b)
L
F
A
X
0
0
0
0
0
0
1
1
0
1
0
1
0
1
1
1
1
0
0
0
1
0
1
1
1
1
0
0
1
1
1
0
1 mark
1 mark
1 mark
1 mark
[4]
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541
Mark Scheme
GCE O LEVEL – May/June 2014
Syllabus
7010
Paper
11
1 mark per correct column.
number
product
value
5
1
5
(5)
5
4
(5)
20
3
(5)
60
2
(5)
120
1
(5)
(120)
0
OUTPUT
5, 120
[4]
9
(a) 1 mark for correct formula in cell D2, 1 mark for correct formula replication D2 to D7, 1mark
for correct formula in G2 and 1 mark for correct formula replication from G2 to G7 (allow
follow through in both columns D and G).
D
G
1
Volume
change
(litres)
Pressure
change
(bar)
2
= C2 – B2
= F2 – E2
3
= C3 – B3
= F3 – E3
Accept formulas
such as:
4
= C4 – B4
= F4 – E4
SUM(C2 – B2)
5
= C5 – B5
= F5 – E5
6
= C6 – B6
= F6 – E6
(or any example
that actually
works)
7
= C7 – B7
= F7 – E7
[4]
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Mark Scheme
GCE O LEVEL – May/June 2014
(b) B1/2 to B7
C1/2 to C7
}
}
1 mark
G1/2 to G7
}
1 mark
Syllabus
7010
Paper
11
[2]
(c) = SUM(D2:D7)/6
= AVERAGE(D2:D7)
= AVERAGE(D2,D3,D4,D5,D6,D7)
= (D2 + D3 + D4 + D5 + D6 + D7)/6
or
or
or
(d) = MAX(G2:G7)
= MAX(G2,G3,G4,G5,G6,G7)
or
[1]
[1]
10 1 mark for each benefit and 1 mark for each drawback (maximum of 2 marks for each
communication method).
mobile phones
benefit:
– wireless system (so can be used anywhere)
– small, portable device/always with you
– instantaneous (e.g. take photo and immediately transfer file)
– can leave messages if recipient not available
drawback:
– contracts tend to be expensive
– phone calls overseas are very expensive
– out of signal
– battery life poor
– data transfer rate can be slow
– not very large memories
– small screens/keyboards make it more difficult to type/navigate
video conferencing
benefit:
– many people can take part in conference across the world
– can see all delegates on screen (and also talk in synchronised way)
– relatively inexpensive since uses Internet for communications
– can hold meeting of several people at short notice
– no need to pay for travelling/hotels/meeting rooms
– less time wasted travelling to meetings overseas/staff not out of office
– safer – recent increased risk of terrorist attacks
drawback:
– equipment is expensive to buy initially
– quality of sound/picture can be poor (poor reception)
– problems with time zones
– fast internet connection required
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Mark Scheme
GCE O LEVEL – May/June 2014
Syllabus
7010
Paper
11
emails:
benefit:
– can send at any time/recipient can open any time
– inexpensive (same cost worldwide)
– can send large multimedia files
– no need for expensive equipment
– can send to multiple recipients
– can use attachment facility
drawback:
– if recipient doesn’t have correct software, can’t open attachments
– possibility of virus infections/phishing from attachments
– need Internet connection/ISP
– may not get immediate response (ONLY IF REVERSE NOT GIVEN UNDER BENEFIT)
11 (a) Any two from:
– “always on” (no need to dial up each time)
– allows telephones to be used at same time as computer in use
– much faster data transfer rate
– dial up charges per minute of use
[6]
[2]
(b) (i) 1 megabits/second = 0.125 Mbyte/second
20 Mbyte file takes 20/0.125 seconds
i.e. 160 seconds
(if final answer is incorrect, allow 1 mark for calculation)
[2]
(ii) 8 megabits/second = 1 Mbyte/second
20 Mbyte file takes 20/1 seconds
i.e. 20 seconds
allow b(i) divided by 8 as follow through
[1]
(c) 1 mark for each advantage and 1 mark for each disadvantage
advantages:
– no trailing wires
– can use equipment anywhere (if in range)
–
reduced costs since less cabling required
disadvantages:
– limited range
– can be blocked by walls/other obstacles
– increased security risk if not password protected
– slower data transfer rate
[2]
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Mark Scheme
GCE O LEVEL – May/June 2014
Page 10
12 (a)
X
Y
Syllabus
7010
Paper
11
Z
[3]
(b)
0
0
1
1
X
(1 mark)
1
0
0
0
Y
(1 mark)
0
0
0
0
Z
(1 mark)
[3]
(c) (i) E, E, E
Flashing display/digits
ERR
(or the equivalent answer)
[1]
(ii) Any one from:
– a fault in the system
– reading exceeded the value 999
[1]
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Mark Scheme
GCE O LEVEL – May/June 2014
Syllabus
7010
Paper
11
13
(3 and 8 AND 4 and 7 MUST be marked in PAIRS)
(accept the phrases)
[4]
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Mark Scheme
GCE O LEVEL – May/June 2014
Syllabus
7010
Paper
11
14 (a) (i) 9
[1]
(ii) 7
[1]
(b) OR, CO, NJ, AK, NV
(–1 mark for each error: i.e. each omission, each incorrect additional item)
(c) (Area(sq miles) > 100 000)
AND
[2]
(Travel time to work (min) < 25)
< - - - - - - - 1 mark - - - - - - > < - - - - - - - - - - - 1 mark - - - - - - - - - - - - >
Or
(Travel time to work (min) < 25)
AND
(Area(sq miles) > 100 000)
< - - - - - - - - - 1 mark - - - - - - - - > < - - - - - - - - - 1 mark - - - - - - - - - - >
[2]
(i) Ref or Name of State
[1]
(ii) this is unique to for each state
[1]
15 possible marking points:
(award marks for each point up to the maximum of 6)
•
•
•
•
•
•
•
•
initialisation
inputs in the right place
correct loop (while or repeat)
adding up sound levels
finding highest/loudest sound level
counting number of sound levels which have been input
finding the average value
correct outputs (OUTSIDE loop and needs some previous processing)
sample program:
total = 0: highest = 0: count = 0
(1 mark)
input sound
(1 mark)
while sound > 0 do
total = total + sound
if sound > highest then highest = sound
count = count + 1
input sound
(1 mark)
(1 mark)
(1 mark)
(1 mark)
endwhile
average = total/count
(1 mark)
print average, highest
(1 mark)
[6]
© Cambridge International Examinations 2014
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Cambridge International Examinations
Cambridge Ordinary Level
*3178912092*
COMPUTER STUDIES
7010/12
May/June 2014
Paper 1
2 hours 30 minutes
Candidates answer on the Question Paper.
No Additional Materials are required.
READ THESE INSTRUCTIONS FIRST
Write your Centre number, candidate number and name on all the work you hand in.
Write in dark blue or black pen.
You may use an HB pencil for any diagrams, graphs or rough working.
Do not use staples, paper clips, glue or correction fluid.
DO NOT WRITE IN ANY BARCODES.
Answer all questions.
No marks will be awarded for using brand names of software packages or hardware.
At the end of the examination, fasten all your work securely together.
The number of marks is given in brackets [ ] at the end of each question or part question.
The maximum number of marks is 100.
This document consists of 24 printed pages.
IB14 06_7010_12/FP
© UCLES 2014
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2
1
Four health and safety risks are shown in the table below.
Put a tick () in either column 2 or 3 to indicate whether the risk is a health risk or a safety risk.
In column 4, describe a method of removing or reducing the risk. Give a different method for each
risk.
1
2
3
4
risk
health
risk
safety
risk
method of removing or reducing the risk
eye strain
trip hazard
fire
Repetitive Strain
Injury (RSI) in the
wrists
[6]
2
A customer books a flight to Brazil using an online travel agency.
(a) Describe the steps taken by the customer and by the agency when booking the flight online.
[3]
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3
(b) Describe the main differences between batch processing and real time transaction
processing.
[2]
3
(a) Name two items of software needed to run video conferencing. In each case, explain the
purpose of the software.
software item 1
purpose
software item 2
purpose
[4]
(b) The table below has three statements. Each of them is about video conferencing.
One or more of these is a benefit of using video conferencing.
Tick () each statement that is a benefit.
statement
benefit
It is possible to hold meetings at any time.
There is no problem with time zones.
Reduces the “hidden cost” of employees being away from the office.
[1]
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4
(c) A student made the following two statements. Each of them is about video conferencing
hardware.
Explain why both statements are incorrect.
“microphones are used so that delegates can hear what is being said”
“webcams record the images and then transmit them to the other meeting room”
[2]
(d) Describe two drawbacks of using video conferencing.
1
2
[2]
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5
4
A student used the Internet to help with his Chemistry project. He typed the following into a
search engine:
transition + elements
(a) The first two search results listed were:
Chemistry of the transition elements
The elements of transition during computer animation
Considering these two examples, describe one problem when using search engines.
[1]
(b) This search gave the student over 480 000 results (“hits”).
Many of these results were not relevant.
How could the student obtain more relevant results?
[1]
(c) Other than security issues, describe one undesirable feature of using the Internet when
looking for information.
[1]
(d) Describe one benefit of using the Internet to find information.
[1]
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6
5
The following algorithm should:
•
•
•
input ten numbers
output the largest number input
output the average value of the input data
10
largest = 0
20
sum = 0
30
for x = 1 to 10
40
input x
50
if x > largest then x = largest
60
output largest
70
sum = sum + x
80
next x
90
average = sum * 10
100
output average
There are four errors in this algorithm.
Locate these errors and suggest a correction.
error 1
correction
error 2
correction
error 3
correction
error 4
correction
[4]
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7
6
The following diagram shows six descriptions of automatic data capture methods and six terms.
Draw lines to connect each description to the correct term.
reading data directly from hard
copy and converting into electronic/
computer-readable form
biometrics
use of fingerprint scans, retina
scans, face identification, etc. as a
way of identifying a person
uniquely
data logging
recognises spoken word patterns
and compares them to patterns
stored in memory
optical
character
recognition
(OCR)
use of minute electronic devices
(containing microchip and antenna)
that can be read from distances up
to 5 metres
optical mark
recognition
(OMR)
automatic data collection using
sensors
radio
frequency
identification
(RFID)
system that reads pencil or pen
marks on a piece of paper in
pre-determined positions
voice
recognition
[5]
© UCLES 2014
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8
7
A floor turtle uses the following commands:
command
description
FORWARD n
Move n cm in a forward direction
BACKWARD n
Move n cm in a backward (reverse) direction
RIGHT t
Turn right through t degrees
LEFT t
Turn left through t degrees
PENUP
Lift the drawing pen up
PENDOWN
Lower the drawing pen
REPEAT x
Repeat the next set of instructions x times
ENDREPEAT
Finish the REPEAT loop
In the following grid, each of the squares measures 10 cm by 10 cm:
Start
Finish
Complete the set of instructions to draw the shape shown above (in bold lines).
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9
1
PENDOWN
2
REPEAT 2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
[6]
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10
8
In each case below, state which Internet term is being described.
(a) Malicious software installed on a user’s hard drive or a web server; the software re-directs
the user to a fake website without their consent or knowledge.
[1]
(b) Personal Internet journals where a writer enters text about a certain topic; anyone can
comment on the topic.
[1]
(c) Websites designed to promote the building of online communities who share the same
interests; usually free of charge; users can add friends, post messages to each other and
update personal profiles.
[1]
(d) Legitimate-looking email sent to a user in the hope of gathering personal information; as
soon as the recipient clicks on the link in the email (or email attachment) they are sent to a
fake website.
[1]
(e) Software that secretly gathers information by monitoring key presses on a user’s keyboard;
this information is relayed back to the person who sent the software originally.
[1]
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11
9
The five statements below are incomplete. Each statement is about computer animation.
(i)
When producing 3D animation effects,
are used to define the start
point and the end point to allow a smooth transition in the animation.
(ii)
The use of intermediate frames between two images to give the appearance of movement
is called
.
(iii) If one image merges into another different type of image (e.g. a mouse turning into an
alien) this is called
.
(iv)
(v)
is used to generate the final 3D image from the 2D model.
Sometimes
part of an animated character.
are used; these are variables controlling the position of
Complete the five statements above using terms from the following list:
•
•
•
•
•
•
•
•
•
animation
avars
cartoons
key frames
morphing
rendering
stick figures
tweening
wikis
(i)
(ii)
(iii)
(iv)
(v)
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12
10 Study the following flowchart.
START
count = 1
negcount = 0
poscount = 0
neg = 0
pos = 0
zero = 0
INPUT X
Yes
is X < 0 ?
neg = neg + X
negcount =
negcount + 1
pos = pos + X
poscount =
poscount + 1
No
Yes
is X > 0 ?
No
zero = zero + 1
count = count + 1
Yes
is count <=
10 ?
No
negavge = neg/negcount
posavge = pos/poscount
OUTPUT
negavge,
posavge, zero
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13
Complete the trace table for the flowchart using the following data:
0, 3, 5, 6, -4, -1, 0, 0, -4, 10
negcount poscount
neg
pos
zero
count
X
negavge
posavge
[6]
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15
12 Camilo works as a hotel inspector. He travels to hotels in his own country and overseas. He visits
the hotels and then sends back a report to his head office after each hotel visit.
(a) Name three modern electronic devices that Camilo could use to help him with his work.
Give a different reason for your choice of each device.
device 1
reason
device 2
reason
device 3
reason
[6]
(b) Most of the hotels offer wireless Internet (Wi-Fi) in the rooms.
Give two disadvantages of using wireless (Wi-Fi) rather than wired Internet access.
1
2
[2]
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16
13 An algorithm has been written to check that code numbers are valid on input. They must be in the
range 1000 to 9999.
Five hundred codes are being entered and the percentage of entered codes which are incorrect
is output.
There is a flowchart on the opposite page. It has some statements missing.
Complete the flowchart. Use statement numbers only, chosen from the list below.
© UCLES 2014
statement number
statement
1
Incorrect = Incorrect + 1
2
INPUT Code
3
is Number <= 500 ?
4
is Code < 1000 ?
5
is Code > 9999 ?
6
Number = 1
7
Number = Number + 1
8
OUTPUT Percent
9
Percent = Incorrect / 5
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17
START
incorrect = 0
Yes
No
Yes
No
Yes
No
STOP
[4]
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18
14 A spreadsheet has been written to help students with their Chemistry. Chemical elements are
written as:
mass number
X
atomic number
For example, iron is represented as:
56
Fe
26
An atom of a chemical element is made up of protons, neutrons and electrons.
atomic number = number of protons = number of electrons
mass number = atomic number + number of neutrons
The spreadsheet is shown below. Column B contains input values and column C contains
calculation results. Input values for the element iron are shown as an example.
Show what formulas must be in cells C3, C4 and C5:
A
B
C
1
input mass number
56
2
input atomic number
26
3
number of electrons
=
4
number of protons
=
5
number of neutrons
=
[3]
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19
15 (a) State four components of an expert system.
1
2
3
4
[4]
(b) Give an example of the use of an expert system.
[1]
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20
16 An encryption system gives each letter of the alphabet a value:
A = 1, B = 2, C = 3, ……… , Y = 25, Z = 26.
Each letter is stored in a 12-bit binary register. The letter “S” (19th letter) is stored as:
2048 1024 512
0
0
0
256
128
64
32
16
8
4
2
1
0
0
0
0
1
0
0
1
1
A 4-bit register is used to store the encryption key. This register shows how many places the bits
are shifted to the left in the 12-bit register when it is encrypted. So,
8
4
2
1
0
1
0
1
means each bit in the 12-bit register is shifted 5 places to the left and the register now becomes:
2048 1024 512
0
0
1
256
128
64
32
16
8
4
2
1
0
0
1
1
0
0
0
0
0
Therefore, the letter “S” would be transmitted with the 4-bit register and the 12-bit register as
follows:
0
1
0
1
0
0
1
0
0
1
1
0
0
0
0
0
(a) “W” is the 23rd letter of the alphabet.
(i) Show how this letter would be stored in the 12-bit register before encryption:
(ii) The 4-bit register contains the following value:
8
4
2
1
0
1
1
0
Show how the letter “W” is now stored in the 12-bit register in encrypted form:
[2]
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21
(b) Find which letter of the alphabet has been encrypted here. (Show all your working.)
0
0
1
1
0
0
0
0
1
1
0
0
1
0
0
0
[2]
(c) (i) What is the largest encryption key that can be stored in the 4-bit register?
8
4
2
1
(ii) Convert this into denary (base 10).
(iii) If this encryption key were used, what problem would it cause?
[3]
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22
17 (a) Complete the truth table for the following logic circuit:
A
X
B
C
Working
A
B
C
0
0
0
0
0
1
0
1
0
0
1
1
1
0
0
1
0
1
1
1
0
1
1
1
X
[4]
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23
(b) Write the logic statement to describe the following logic circuit:
A
X
B
C
[3]
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18 A school has 1500 students. It is conducting a survey on their music preferences. Each student
uses a computer and inputs their name and then chooses one of 5 options:
•
•
•
•
•
rock (input value 1)
soul (input value 2)
pop (input value 3)
jazz (input value 4)
classical (input value 5)
Write an algorithm, using pseudocode or a flowchart, which:
•
•
•
inputs the choice of all 1500 students (values 1 to 5)
outputs all the names of the students who chose classical music
outputs the percentage who chose each option.
[5]
Permission to reproduce items where third party owned material protected by copyright is included has been sought and cleared where possible. Every
reasonable effort has been made by the publisher (UCLES) to trace copyright holders, but if any items requiring clearance have unwittingly been included, the
publisher will be pleased to make amends at the earliest possible opportunity.
Cambridge International Examinations is part of the Cambridge Assessment Group. Cambridge Assessment is the brand name of University of Cambridge Local
Examinations Syndicate (UCLES), which is itself a department of the University of Cambridge.
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CAMBRIDGE INTERNATIONAL EXAMINATIONS
GCE Ordinary Level
MARK SCHEME for the May/June 2014 series
7010 COMPUTER STUDIES
7010/12
Paper 1, maximum raw mark 100
This mark scheme is published as an aid to teachers and candidates, to indicate the requirements of
the examination. It shows the basis on which Examiners were instructed to award marks. It does not
indicate the details of the discussions that took place at an Examiners’ meeting before marking began,
which would have considered the acceptability of alternative answers.
Mark schemes should be read in conjunction with the question paper and the Principal Examiner
Report for Teachers.
Cambridge will not enter into discussions about these mark schemes.
Cambridge is publishing the mark schemes for the May/June 2014 series for most IGCSE, GCE
Advanced Level and Advanced Subsidiary Level components and some Ordinary Level components.
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Mark Scheme
GCE O LEVEL – May/June 2014
Page 2
1
Paper
12
1 mark for health column and 1 mark for safety column; award 1 mark for a correct method of
minimising risk
risk
health
risk
eye strain
fire
RSI in the wrists
safety
risk
Total 2 marks
–1 for each error
way of eliminating or minimising the risk
–
–
–
–
trip hazard
2
Syllabus
7010
use of sufficiently large screen
use LCD (non-flicker) monitors
take (regular) breaks
use anti-glare screen covers/filters
– example of removal of trailing wires e.g. use cable
ducts, use cable ties
– use WiFi wherever possible
– example of cooling e.g. well ventilated, don’t cover
vents on equipment
– don’t overload wall sockets
– no liquids near the computer
– maintain equipment properly allow examples
–
–
–
–
set seat to correct height/position
use wrist supports/wrists positioned correctly
ergonomic keyboards
take (regular) breaks
1 mark for each named (different) method
mark not dependent on correct identification of risk
[6]
(a) Any three from:
– logs on/accesses the travel agency website
– enter/access personal details (accept two or more suitable examples of details)
– select/enter flight requirements (accept two or more suitable examples of requirements)
– view available flights
– make the booking
– confirmation sent
[3]
(b) batch processing
Any one from:
– all data (collected together before) processed in one go
– no human interaction required once processing started
– system not time sensitive
real time transaction processing
Any one from:
– requires immediate/quick response
– updates as data input/received
[2]
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572
Mark Scheme
GCE O LEVEL – May/June 2014
Syllabus
7010
Paper
12
(a) 1 mark for naming software + 1 mark for a matching purpose
software:
purpose:
codec
– converts (and compresses) analogue data into digital data
software:
purpose:
(vide/audio) compression software
– reduces amount of (video/audio) data being transmitted
software
purpose:
echo cancellation software
– allows talking in real time
– prevents feedback/sound from speakers being picked up by microphone [4]
(b)
statement
advantage
it is possible to hold meetings at any time
there is no problem with time zones
reduces the “hidden cost” of employees being away from the office
[1]
(c) 1 mark for reason why each statement is incorrect:
– microphone only pick up sound/input device
– loudspeakers needed to produce the sound/voices for delegates to hear
– webcams do not record any data/video
– webcams (only) capture data/video
– webcams do not transmit data/video
[2]
(d) Any two from:
– expensive to set up
– poor quality of sound/video or need fast internet connection
– time zones can cause problems/differences in time zones
[2]
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Mark Scheme
GCE O LEVEL – May/June 2014
Page 4
4
Syllabus
7010
Paper
12
(a) Any one from:
– search engine can pick up unrelated websites
– can result in too many “hits”
[1]
(b) Any one from:
– narrow down the search criteria
– e.g. chemistry transition element
– use of “…” around key words
[1]
(c) – pornographic/objectionable websites can be found
– unreliable/unnecessary information
– unwanted advertisements/pop-ups
[1]
(d) Any one from:
– faster/easier to do a search rather than looking at, e.g., several book indexes
– information more up-to-date
– can cut and paste information directly into a document
5
[1]
1 mark for identification of error and suggested correction (description or corrected pseudocode)
error:
correction:
number
line 40: input x; using same input value as loop variable will cause problems or line
30: for x = 1 to 10
change loop variable e.g. for count = 1 to 10 or change input variable e.g. input
error:
correction:
line 50: formula is reversed
…. then largest = x (or largest = number)
error:
correction:
line 60: output shouldn’t be inside the loop
100 output average, largest
error:
correction:
line 90: incorrect formula
average = sum/10
[4]
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574
Mark Scheme
GCE O LEVEL – May/June 2014
Syllabus
7010
Paper
12
1 mark for each correct link up to maximum of 5 marks
reading data directly from hard copy
and converting into electronic/
computer-readable form
biometrics
use of fingerprint scans, retina scans,
face identification, etc. as a way of
identifying a person uniquely
data logging
recognises spoken word patterns and
compares them to patterns stored in
memory
optical character
recognition (OCR)
use of minute electronic devices
(containing microchip and antenna)
that can be read from distances up to
5 metres
optical mark recognition
(OMR)
automatic data collection using
sensors
radio frequency
identification (RFID)
system that reads pencil or pen marks
on a piece of paper in pre-determined
positions
voice recognition
[5]
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575
Mark Scheme
GCE O LEVEL – May/June 2014
Syllabus
7010
Paper
12
1 mark for each block of code between dotted lines. (e.g. use of REPEAT and BACKWARD
functions). If an error occurs in the code, try to find a correct code sequence later on in the
answer (in cases such as this, it is often easier to work backwards from last statement looking for
correct blocks).
PENDOWN
REPEAT 2
3 FORWARD 50
FORWARD 25 ENDREPEAT
4 RIGHT 90
RIGHT 90 FORWARD 50
5 ENDREPEAT
RIGHT 90
----------------------------------6 FORWARD 10
7 RIGHT 90
8 FORWARD 20
---------------9 PENUP
(statements 9 and 10 are interchangeable)
10 LEFT 90
11 FORWARD 10
---------------12 PENDOWN
13 LEFT 90
(statements 12 and 13 are interchangeable)
14 FORWARD 20
15 RIGHT 90
---------------16 FORWARD 10
17 RIGHT 90
18 FORWARD 40
---------------19 LEFT 90
20 FORWARD 20
(21 PENUP)
(line 21 is not essential)
8
[6]
(a) pharming
[1]
(b) blog(s)
[1]
(c) social networking (sites)
[1]
(d) phishing
[1]
(e) spyware/key logging (software)
[1]
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Mark Scheme
GCE O LEVEL – May/June 2014
Page 7
9
Syllabus
7010
Paper
12
1 mark per point
(i) key frames
(ii) tweening
(iii) morphing
(iv) rendering
(v) avars
[5]
10 (NOTES: Additional 0s in any column (UNLESS THEY ARE JUST THE REPEAT OF 0 VALUES)
lose the mark for that column
If columns 1 to 7 are wrong there can be one mark for initialisation (0 0 0 0 0 1) and a mark for
the correct output -3, 6).
negcount
poscount
neg
pos
zero
count
X
0
0
0
0
0
1
1
2
0
1
3
3
3
2
8
4
5
3
14
5
6
1
–4
6
–4
2
-5
7
–1
2
8
0
3
9
0
10
–4
11
10
3
–9
4
24
< - - - - - - 1 mark - - - - - > 1 mark
1 mark
negavge
posavge
–3
6
1 mark <- - - -1 mark - - - -> < - - - - - 1 mark - - - - >
[6]
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Mark Scheme
GCE O LEVEL – May/June 2014
Syllabus
7010
Paper
12
12 (a) 1 mark for device + 1 mark for reason all reasons must be different
device
reason
digital camera
– to photograph the hotels/ hotel rooms/facilities
– to video the hotels/hotel rooms/facilities
GPS system
– to find his way to hotel by car/on foot
Mobile/smart phone
– keep in contact with office/store important numbers
– phone hotel to arrange a visit
– use of internet if wifi not available
– to photograph the hotels/ hotel rooms/facilities
– to video the hotels/hotel rooms/facilities
– to find his way to hotel by car/on foot
portable computer
e.g. tablet, laptop
– to type his reports (about the hotels)
– send emails/photos (back to the office)
– allow VoIP/cam-to-cam communications
– allow instant messaging
– so he can access the Internet and find out details
about the hotel he is visiting
PDA
– to store meeting details/details about hotels
– to store contact details
Mobile internet dongle/
– to provide access to the internet router/broadband modem
Memory stick
– to save/backup reports
[6]
(b) Any two from:
– slower data transfer rate
– less secure network unless password protected e.g. increased risk of hacking
– signal often poor/drop out is common
– greater latency
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Mark Scheme
GCE O LEVEL – May/June 2014
Syllabus
7010
Paper
12
13
[4]
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Mark Scheme
GCE O LEVEL – May/June 2014
Page 11
Syllabus
7010
Paper
12
14 1 mark for each working formula in cells C3, C4, and C5.
A
B
C
1
input mass number
56
2
input atomic number
26
3
number of electrons =
= B2
4
number of protons =
= B2 (or = C3)
5
number of neutrons =
= B1 – B2
[3]
15 (a) 1 mark for each item:
–
–
–
–
–
–
knowledge base
rule(s) base
inference engine
(expert system) shell
explanation system
user interface/HCI
[4]
(b) Any one from:
–
–
–
–
–
–
–
chess/strategy games
prospecting for oil/minerals
medical diagnosis
engine diagnostics
television/computer/electronic diagnostics
financial/tax advice
career advice
[1]
16 (a) (i) 1 mark for correct binary numbers
0
0
0
0
0
0
0
1
0
1
1
1
1
0
0
0
0
0
0
(ii) 1 mark for correct binary numbers
0
1
0
1
1
[2]
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Mark Scheme
GCE O LEVEL – May/June 2014
Page 12
Syllabus
7010
Paper
12
(b) one mark
– letter “Y” or 25th letter
One mark
– the binary number 0 0 0 0 1 1 0 0 1 0 0 0 has been shifted (to the left) 3 places
– so the binary number becomes 0 0 0 0 0 0 0 1 1 0 0 1
– 1+8+16
[2]
(c) (i) 1 1 1 1
(ii) 15 (allow follow through from (i))
(iii) – try to move 15 places to the left which is not possible
– only 12 bits in register to store letter; 15 is too large
– you would end up with 12 0s in the register
[3]
17 (a)
A
B
C
X
0
0
0
1
0
0
1
1
0
1
0
0
0
1
1
1
1
0
0
1
1
0
1
1
1
1
0
0
1
1
1
0
1 mark
1 mark
1 mark
1 mark
[4]
S
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Mark Scheme
GCE O LEVEL – May/June 2014
Page 13
(b) ( A = NOT 1 )
Syllabus
7010
Paper
12
1 mark
OR
1 mark
(( A = 1 OR B = 1) AND C = 1 )
1 mark
Accept:
A
+
(( A + B ). C )
or
A
+
( A + B ). C
Accept:
A’
+
(( A + B ). C )
or
A’
+
( A + B ). C
(1 mark)
(1 mark)
(1 mark)
(NOT A)
OR
(( A OR B ).AND C )
(1 mark)
(1 mark)
(1 mark)
Accept:
[3]
18 marking points:
•
•
•
•
•
•
•
•
•
initialisation of all 5 totals
loop to control input for all 1500 students
input choice and name of student inside the loop
check student choice …
… increment the appropriate total
output name of student who likes classical music
find the 5 percentages (either using /15 or (*100/1500)) outside the loop
output the 5 percentages outside the loop (must have some processing)
error checking
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Mark Scheme
GCE O LEVEL – May/June 2014
Syllabus
7010
Paper
12
sample algorithm (in pseudocode)
NOTE: many students may make use of the case … of … endcase construct here rather than five IF
statements
rock = 0: soul = 0: pop = 0: jazz = 0: classical = 0
1 mark
for student = 1 to 1500
1 mark
input choice, pupil name
if choice = 1 then rock = rock + 1
if choice = 2 then soul = soul + 1
if choice = 3 then pop = pop + 1
if choice = 4 then jazz = jazz + 1
if choice = 5 then classical = classical + 1
if choice = 5 then output pupil name
next student
percent1 = rock/15
percent2 = soul/15
percent3 = pop/15
percent4 = jazz/15
percent5 = classical/15
output percent1, percent2, percent3, percent4, percent5
(sample pseudocode showing a possible case … of construct:
(alternative to rows 4 to 9 in above algorithm)
case of choice:
1: rock = rock + 1
2: soul = soul + 1
3: pop = pop + 1
4: jazz = jazz + 1
5: classical = classical + 1
output pupil name
endcase)
1 mark
2 marks
1 mark
1 mark
1 mark
2 marks
1 mark
[5]
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Cambridge International Examinations
Cambridge Ordinary Level
* 8 8 5 0 4 1 6 5 8 5 *
7010/12
COMPUTER STUDIES
Paper 1
October/November 2014
2 hours 30 minutes
Candidates answer on the Question Paper.
No Additional Materials are required.
READ THESE INSTRUCTIONS FIRST
Write your Centre number, candidate number and name on all the work you hand in.
Write in dark blue or black pen.
You may use an HB pencil for any diagrams, graphs or rough working.
Do not use staples, paper clips, glue or correction fluid.
DO NOT WRITE IN ANY BARCODES.
Answer all questions.
No marks will be awarded for using brand names of software packages or hardware.
At the end of the examination, fasten all your work securely together.
The number of marks is given in brackets [ ] at the end of each question or part question.
This document consists of 23 printed pages and 1 blank page.
DC (LEG/CGW) 100859
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1
State three features of a typical operating system.
1 ......................................................................................................................................................
.........................................................................................................................................................
2 ......................................................................................................................................................
.........................................................................................................................................................
3 ......................................................................................................................................................
..................................................................................................................................................... [3]
2
Many companies across the world have increasingly introduced computer systems into the office
environment. This has had a big effect on employees.
(a) Identify three ways in which this new technology has affected employees. In each case,
explain why it has had an impact.
1 ...............................................................................................................................................
..................................................................................................................................................
impact ......................................................................................................................................
..................................................................................................................................................
..................................................................................................................................................
2 ...............................................................................................................................................
..................................................................................................................................................
impact ......................................................................................................................................
..................................................................................................................................................
..................................................................................................................................................
3 ...............................................................................................................................................
..................................................................................................................................................
impact ......................................................................................................................................
..................................................................................................................................................
.............................................................................................................................................. [6]
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(b) Describe two health risks associated with increased use of computers.
1 ................................................................................................................................................
...................................................................................................................................................
...................................................................................................................................................
2 ................................................................................................................................................
...................................................................................................................................................
...............................................................................................................................................[2]
3
The following five statements about Internet security are incomplete:
(i)
Illegal access to a computer system is known as < - - - - (a) - - - - >.
(ii)
< - - - - (b) - - - - > are programs that self-replicate (copy themselves) and are designed to
disrupt computer systems.
(iii)
< - - - - (c) - - - -> is where a user is sent legitimate-looking emails; as soon as the email is
opened and the recipient clicks on the embedded link, they are sent to a fake website.
(iv)
Software that monitors key presses on a user’s keyboard, and relays the information back to
the person who sent the software, is known as < - - - - (d) - - - - >.
(v)
< - - - - (e) - - - - > is malicious code or software installed on the hard drive of a user’s
computer or on a web server; the code or software will re-direct the user to a fake website
without their knowledge.
Complete the five statements using words from the following list:
•
•
•
•
•
•
•
•
cookies
hacking
pharming
phishing
spam
spyware
viruses
web browsers
(a) .................................................................................................................................................[1]
(b) .................................................................................................................................................[1]
(c) .................................................................................................................................................[1]
(d) .................................................................................................................................................[1]
(e) .................................................................................................................................................[1]
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4
Six statements and six values are shown below.
Each statement will generate one possible value.
Draw a line to link each statement to its correct value.
statement
value
number of times the following
loop operates:
count = 1
repeat
input x
count = count + 1
until count = 5
1
the number of bits that make up
a byte
base 10 (denary) value of the
following binary number:
32
16
8
4
2
1
0
0
1
1
1
1
4
5
8
the number of tracks on the
single side of a CD-R
number of minutes to upload a
75 Mbyte file at 2 megabits/
second upload speed
10
X
If there are 2 bytes in a Kbyte,
what is the value of X?
15
[5]
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5
Johan wants to write an article on how Satellite Navigation systems (Sat Nav) use GPS technology.
(a) He sends out a questionnaire to find out people’s knowledge of how these systems work.
Three of the questions on his questionnaire are shown below:
TRUE
FALSE
Sat Nav accurately measures vehicle speed using satellite position
TRUE
and accurate timing
FALSE
TRUE
FALSE
Sat Nav devices send signals to the global positioning satellites
Satellites tell the Sat Nav which direction the vehicle should take
Put a circle around TRUE or FALSE for each of the three questions to indicate the correct
answers Johan should receive.
[3]
(b) Johan also wants to include an explanation as to why Sat Nav systems sometimes give
incorrect instructions.
Give two reasons why this might occur.
1 ................................................................................................................................................
...................................................................................................................................................
2 ................................................................................................................................................
...............................................................................................................................................[2]
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6
The following section of a pseudocode algorithm should:
•
•
•
•
input 500 numbers
generate a ratio called k
output each value of k
output how many numbers were larger than 10
10
20
30
40
50
60
70
80
total = 1
FOR x = 1 TO 500
IF number < 10 THEN total = total + 1
k = x / number
x = x + 1
OUTPUT k
NEXT x
OUTPUT x
(a) There are five errors in the above code.
Locate these errors and suggest a correction.
error 1 .......................................................................................................................................
correction ..................................................................................................................................
...................................................................................................................................................
error 2 .......................................................................................................................................
correction ..................................................................................................................................
...................................................................................................................................................
error 3 .......................................................................................................................................
correction ..................................................................................................................................
...................................................................................................................................................
error 4 .......................................................................................................................................
correction ..................................................................................................................................
...................................................................................................................................................
error 5 .......................................................................................................................................
correction ..................................................................................................................................
...............................................................................................................................................[5]
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(b) The corrected algorithm was converted to a computer program and run. However, after
several numbers were input, the program stopped and an error message was generated,
showing that there was a further error at line 40 (k = x / number).
State what could cause this error to occur.
...................................................................................................................................................
...................................................................................................................................................
Suggest a change to line 40 to overcome this problem.
...................................................................................................................................................
...................................................................................................................................................
...............................................................................................................................................[2]
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7
A digital camera contains a microprocessor. The camera’s specification includes:
•
•
•
20 megapixel resolution
32 gigabyte memory card
autofocus facility
(a) A more expensive model of the camera has 40 megapixel resolution.
(i)
Describe one advantage of increasing the resolution.
...........................................................................................................................................
.......................................................................................................................................[1]
(ii)
Describe one disadvantage of having 40 megapixel resolution.
...........................................................................................................................................
.......................................................................................................................................[1]
(b) (i)
Describe the type of memory used in the memory card.
...........................................................................................................................................
.......................................................................................................................................[1]
(ii)
Give one benefit of using this type of memory.
...........................................................................................................................................
.......................................................................................................................................[1]
(c) (i)
What is the meaning of the term pixel?
...........................................................................................................................................
.......................................................................................................................................[1]
(ii)
If a compressed image file requires an average of 1 byte per pixel, what is the maximum
number of photos that can be stored on the memory card?
...........................................................................................................................................
.......................................................................................................................................[1]
(d) Apart from autofocus, describe one other feature you would expect to see on a digital camera
controlled by a microprocessor.
...................................................................................................................................................
...............................................................................................................................................[1]
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8
The doors on a train are opened and closed automatically. Motors are used to operate the doors.
The system is controlled by a microprocessor.
Each door has a sensor which detects if a passenger enters or leaves the train as the doors are
closing. If a passenger is detected, the doors are automatically re-opened.
(a) Name a sensor which could be used to detect a passenger.
...............................................................................................................................................[1]
(b) If the sensor in one of the doors fails, describe a safety mechanism to prevent injury to a
passenger.
...................................................................................................................................................
...................................................................................................................................................
...............................................................................................................................................[1]
(c) Describe how the sensors, microprocessor and door motors interact to ensure a passenger
is not trapped in a closing door.
...................................................................................................................................................
...................................................................................................................................................
...................................................................................................................................................
...................................................................................................................................................
...................................................................................................................................................
...................................................................................................................................................
...................................................................................................................................................
...................................................................................................................................................
...................................................................................................................................................
...............................................................................................................................................[4]
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9
A floor turtle uses the following commands:
Command
Description
FORWARD n
Move n cm in a forward direction
BACKWARD n
Move n cm in a backward (reverse) direction
RIGHT t
Turn right through t degrees
LEFT t
Turn left through t degrees
PENUP
Lift the drawing pen up
PENDOWN
Lower the drawing pen
REPEAT x
Repeat the next set of instructions x times
ENDREPEAT
Finish the REPEAT loop
In the following grid, each of the squares represents 10 cm by 10 cm:
Finish
Start
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11
Complete the set of instructions to draw the shape shown on the left:
1 PENDOWN
2 LEFT 90
3 REPEAT 2
4---------------------------5---------------------------6---------------------------7---------------------------8---------------------------9---------------------------10 - - - - - - - - - - - - - - - - - - - - - - - - - - - 11 - - - - - - - - - - - - - - - - - - - - - - - - - - - 12 - - - - - - - - - - - - - - - - - - - - - - - - - - - 13 - - - - - - - - - - - - - - - - - - - - - - - - - - - 14 - - - - - - - - - - - - - - - - - - - - - - - - - - - 15 - - - - - - - - - - - - - - - - - - - - - - - - - - - 16 - - - - - - - - - - - - - - - - - - - - - - - - - - - 17 - - - - - - - - - - - - - - - - - - - - - - - - - - - 18 - - - - - - - - - - - - - - - - - - - - - - - - - - - 19 - - - - - - - - - - - - - - - - - - - - - - - - - - - 20 - - - - - - - - - - - - - - - - - - - - - - - - - - - 21 - - - - - - - - - - - - - - - - - - - - - - - - - - - 22 - - - - - - - - - - - - - - - - - - - - - - - - - - - 23 - - - - - - - - - - - - - - - - - - - - - - - - - - - 24 - - - - - - - - - - - - - - - - - - - - - - - - - - - 25 - - - - - - - - - - - - - - - - - - - - - - - - - - - -
[6]
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10 (a) The flowchart on the next page shows how barcodes are used in a supermarket to find
product information and to produce orders for new stock automatically. Several statements
are missing from the flowchart.
Complete the flowchart, using item numbers only from the list below.
Item
number
© UCLES 2014
Description
1
is barcode found?
2
is barcode read?
3
is flag for this product = 1?
4
is number in stock <= re-order value?
5
key in the barcode manually
6
locate price and product information from file
7
output an error message
8
output order request for new stock
9
output receipt and itemised bill
10
reduce number in stock by 1 and write new value back to the record
11
search database for barcode
12
set flag for this product to 1
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START
No
any more
barcodes to
scan?
Yes
scan barcode
STOP
No
Yes
No
Yes
Yes
No
No
Yes
[8]
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(b) Two devices used by the supermarket Point-Of-Sale (POS) terminal are a barcode reader
and a keyboard.
Name two other input/output devices used at the POS and give a use for each device.
device 1 ....................................................................................................................................
use ............................................................................................................................................
...................................................................................................................................................
...................................................................................................................................................
device 2 ....................................................................................................................................
use ............................................................................................................................................
...................................................................................................................................................
...............................................................................................................................................[4]
11 A spreadsheet was set up to find the value of gold jewellery. The purity of gold is measured in
carats. Gold that is 24 carat is 100% pure. Other purities are measured as fractions of 24 carat. For
18
× 100 = 75% pure. Therefore, 20 grams of 18 carat jewellery would
example, 18 carat gold is
24
18
× 20 = 15 grams of pure gold.
contain
24
A
B
C
D
1
input number of
carats of gold
2
3
input weight of the
jewellery (in grams)
4
actual weight of gold
(grams)
5
input value of gold
($ per gram)
6
total value of gold
($)
Values are input into cells B2, B3 and B5 and output is shown in cells C4 and C6.
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(a) Cell C4 calculates the actual weight of gold in the original jewellery.
What formula would you expect to be in cell C4?
= ............................................................................................................................................[1]
(b) Cell C6 calculates the value of the gold content of the jewellery.
What formula would you expect to be in cell C6?
= ............................................................................................................................................[1]
(c) It was decided to include an extra input in D1. This additional input was the original amount
paid for the gold jewellery (in $). Cell D6 will now show whether the current sale value of the
gold jewellery would generate a profit or not.
Complete the following formula in cell D6:
= IF (………………………… , " ……………….……… ", "no profit")
[2]
(d) A buyer bought some 18 carat gold jewellery for $1500. The jewellery weighed 60 grams. The
value of gold is $40 per gram.
Show the values you would expect to see in cells B2, B3, B5, C4, C6, D1 and D6 using the
following spreadsheet page:
A
B
C
amount paid for
jewellery ($)
1
input number of
carats of gold
2
3
4
input weight of the
jewellery (in grams)
6
input value of gold
($ per gram)
total value of gold
($)
………………………
………………………
………………………
actual weight of gold
(grams)
5
D
………………………
………………………
……………………… ………………………
[3]
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12 An advertising sign uses large LED characters controlled by a microprocessor.
Each letter is formed from a grid made up of eight rectangles numbered 1 to 8:
1
2
3
4
5
6
7
8
For example, the letter “Z” is formed as follows:
1
2
4
5
7
8
Each rectangle has six LEDs that can light up; these LEDs are labelled “a” to “f”:
a
e
d
b
f
c
The LEDs in a rectangle can be represented in a 6-bit register. For example, rectangle 3 of the
letter “Z”:
a
e
can be represented as:
f
0
e
1
d
0
c
0
b
0
a
1
Thus the letter “Z” can be represented by the 8 registers:
1
5
© UCLES 2014
2
4
7
8
1
2
3
4
5
6
7
8
f
0
0
0
0
0
0
0
0
e
0
0
1
0
0
1
0
0
d
0
0
0
0
0
0
0
0
c
0
0
0
0
0
1
1
0
b
0
0
0
0
0
0
0
0
a
0
1
1
0
0
0
0
0
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(a) Show how the letter “E” can be represented by the eight 6-bit registers (four registers have
been done for you).
f
e
d
c
b
a
0
0
0
0
0
0
1
2
3
1
2
3
4
5
6
7
8
0
0
0
0
0
0
4
0
0
0
0
0
0
5
6
7
0
0
0
0
0
0
8
[4]
(b) State which letter of the alphabet is represented by the following eight 6-bit registers.
f
e
d
c
b
a
0
0
0
0
0
0
1
0
0
1
0
0
0
2
0
0
0
0
1
0
3
0
0
0
0
0
0
4
0
0
0
0
0
0
5
0
0
1
0
0
1
6
0
0
0
0
1
1
7
0
0
0
0
0
0
8
letter ……………………………………
[2]
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13 (a) Complete the truth table for the following logic circuit:
A
B
X
C
A
B
C
0
0
0
0
0
1
0
1
0
0
1
1
1
0
0
1
0
1
1
1
0
1
1
1
Working
X
[4]
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(b) Re-draw the logic circuit shown opposite, using NAND and NOR gates only.
[2]
(c) Write a logic statement that describes the following logic circuit:
A
B
X
C
...................................................................................................................................................
...................................................................................................................................................
...................................................................................................................................................
...................................................................................................................................................
...............................................................................................................................................[3]
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14 Study the following flowchart very carefully.
START
sum1 = 0
sum2 = 0
total = 0
INPUT a, b, c, d, e, f
Yes
is a = 0 and
b = 0?
STOP
No
sum1 = a*6 + b*5 + c*4
sum2 = d*3 + e*2 + f*1
total = sum1 + sum2
total = total – 11
is total = 0?
Yes
OUTPUT “data are OK”
No
No
© UCLES 2014
is total < 0?
Yes
OUTPUT “error”
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Complete the trace table for this flowchart using the following data:
4, 3, 2, 0, 0, 8
5, 0, 1, 2, 3, 4
0, 0, 0, 0, 0, 0
sum1
sum2
total
a
b
c
d
e
f
OUTPUT
[5]
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15 The following statement was produced using a word processor.
In New York City, all the taxis are painted yelow.
This colour scheme for these taxis goes back many years.
Taxis have to be changed every 3 years for safety reasons.
All instructions inside the taxis are in English and Spanish since this is a dual
language city.
Four changes were made to the original document using built-in word processing features. Note
that all the changes are shown in shaded text.
In New York City, all the cabs are painted yellow.
This colour scheme for these cabs goes back many years.
Cabs have to be replaced every 3 years for safety reasons.
Todas las instrucciones dentro de los taxis están en inglés y español puesto que esto
es una ciudad dual de la lengua.
Describe four different word processing features that could have been used to make these
changes.
1 .......................................................................................................................................................
..........................................................................................................................................................
..........................................................................................................................................................
2 .......................................................................................................................................................
..........................................................................................................................................................
..........................................................................................................................................................
3 .......................................................................................................................................................
..........................................................................................................................................................
..........................................................................................................................................................
4 .......................................................................................................................................................
..........................................................................................................................................................
......................................................................................................................................................[4]
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16 A school has 3000 students sitting final examinations.
Each student sits eight examinations.
Write an algorithm, using pseudocode or a flowchart, which:
•
•
•
inputs the marks for all 8 examinations for each student
outputs for each student the average mark for their 8 examinations
outputs the highest mark overall
..........................................................................................................................................................
..........................................................................................................................................................
..........................................................................................................................................................
..........................................................................................................................................................
..........................................................................................................................................................
..........................................................................................................................................................
..........................................................................................................................................................
..........................................................................................................................................................
..........................................................................................................................................................
..........................................................................................................................................................
..........................................................................................................................................................
..........................................................................................................................................................
..........................................................................................................................................................
..........................................................................................................................................................
..........................................................................................................................................................
..........................................................................................................................................................
..........................................................................................................................................................
..........................................................................................................................................................
..........................................................................................................................................................
..........................................................................................................................................................
..........................................................................................................................................................
..........................................................................................................................................................
......................................................................................................................................................[5]
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CAMBRIDGE INTERNATIONAL EXAMINATIONS
Cambridge Ordinary Level
MARK SCHEME for the October/November 2014 series
7010 COMPUTER STUDIES
7010/12
Paper 1, maximum raw mark 100
This mark scheme is published as an aid to teachers and candidates, to indicate the requirements of
the examination. It shows the basis on which Examiners were instructed to award marks. It does not
indicate the details of the discussions that took place at an Examiners’ meeting before marking began,
which would have considered the acceptability of alternative answers.
Mark schemes should be read in conjunction with the question paper and the Principal Examiner
Report for Teachers.
Cambridge will not enter into discussions about these mark schemes.
Cambridge is publishing the mark schemes for the October/November 2014 series for
most Cambridge IGCSE®, Cambridge International A and AS Level components and some
Cambridge O Level components.
® IGCSE is the registered trademark of Cambridge International Examinations.
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Mark Scheme
Cambridge O Level – October/November 2014
Page 2
1
Paper
12
Any three from:
–
–
–
–
–
–
–
–
–
–
–
–
–
–
–
2
Syllabus
7010
(provides) user interface
input/output control
security
handling interrupts
spooling
memory management
processor management
utilities (e.g. copy, save, delete, re-name, etc.)
maintain user accounts
load/run software
error reporting/handling
multiprogramming
batch processing (JCL)/real time processing
multitasking/multiuser/multi-access
file management
[3]
(a) 1 mark for way + 1 mark for reason
way
–
deskilling
–
–
(re-)training
–
–
redundancy
–
–
work from home (etc.)
–
–
nicer/safer work place
–
–
health (& safety)
–
impact
software has removed the need for some of the
more traditional skills e.g. using CAD
work practices have changed; need to learn how to
use the new software/computer
new technology allows work to be completed by
fewer staff/out-sourced to “cheaper” work forces in
foreign countries
use of emails, VoIP, video conferencing, instant
messaging, etc. allows working away from the office
quieter (no noisy typewriters) and safer (no heavy
filing cabinets)
RSI, headaches, backaches
[6]
(b) Any two health risks from:
–
–
–
3
(a)
(b)
(c)
(d)
(e)
RSI in wrists or fingers from prolonged typing or repeated clicking of mouse button
headaches/eyestrain/dry eye from staring at a monitor for long periods of time/glare from
monitor
back ache/strain from sitting in same position for a long time/using chair with no
adjustment
[2]
hacking
viruses
phishing
spyware
pharming
[1]
[1]
[1]
[1]
[1]
© Cambridge International Examinations 2014
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Mark Scheme
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Page 3
4
Syllabus
7010
Paper
12
1 mark for each correct connection up to the maximum of 5
number of times the following loop
operates:
count = 1
repeat
input ×
count = count + 1
until count = 5
1
the number of bits that make up a
byte
base 10 (denary) value of the
following binary number:
32
0
16
0
8
4
1
1
2
1
4
1
5
1
the number of tracks on single side
of a CD-R
8
number of minutes to upload a 75
Mbyte file at 2 megabits/second
upload speed
If there are 2
x
10
bytes in a Kbyte,
15
what is the value of x?
[5]
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Mark Scheme
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Page 4
5
Syllabus
7010
Paper
12
(a)
Sat Nav devices send signals to the global positioning
satellites
TRUE
FALSE
Sat Nav accurately measures vehicle speed using satellite
position and accurate timing
TRUE
FALSE
Satellites tell the Sat Nav which direction the vehicle
should take
TRUE
FALSE
[3]
(b) Any two from:
–
–
–
6
software/maps not up to date/new road
loss of satellite signals
wrong data input by user (e.g. start point and end point)
[2]
(a) 1 mark for each error and suggested correction (accept description or example of corrected
pseudocode).
error:
correction:
line 10: total = 1
totals should be set to zero; total = 0
error:
correction:
line 30: … number < 10 …
check should be made if number > 10; … number > 10 …
error:
correction:
no input inside loop
input number
error:
correction:
line 50: x = x + 1
for … to loops don’t need a counter; remove line 50 altogether
error:
correction:
line 80: output x
output should be total value; output total
[5]
(b) division by zero error (or similar description of error produced when dividing by 0)
add an error trap after input of number
e.g. 40 if number = 0 then k = 0 else k = x/number
[2]
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Page 5
7
(a) (i) –
–
(ii) –
–
–
Syllabus
7010
Paper
12
higher quality photos
when “blown up” less likely for photo to “pixelate”
[1]
uses up more memory (on card)
takes longer to upload/download a photo
file size will be greater
[1]
(b) (i) –
–
–
(ii) –
–
–
(c) (i) –
(ii) –
solid state memory
flash drive
non-volatile
[1]
no moving parts (so more robust)
can be removed from camera and retain its contents
can erase contents and reuse memory card
[1]
(pic)ture (el)ement
[1]
819 or 1638
[1]
(d) Any one point from: e.g.
–
–
–
–
–
–
8
auto flash
anti (hand) shake facility
easy deletion of unwanted photos
ability to “manipulate” images after they have been taken/special effects
“smart” operation e.g. automatically pick out objects, faces, etc.
auto capture
[1]
(a) Any one from:
–
–
–
infra red (sensor)
pressure (sensor)
proximity (sensor)
[1]
(b) Any one from:
–
–
–
additional sensors used
door defaults to open position
sounds an alarm if a sensor fails
[1]
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Cambridge O Level – October/November 2014
Page 6
Syllabus
7010
Paper
12
(c) Any four points from:
– sensors continuously send signals/data
– sensor sends signals/data sent to the microprocessor
– signal converted to digital if necessary (using ADC)
– microprocessor checks which door(s) is (are) affected
– microprocessor compares sensor reading with stored values
– if reading indicates passenger detected…
– …microprocessor sends signal/data to actuators/motor…
– (converted to analogue using DAC)
– …to operate motors to open doors
– microprocessor also send signal to driver’s cab (automatically) to sound an alarm
– monitoring continues until system switched off
9
1
2
3
4
5
6
PENDOWN
LEFT 90
REPEAT 2
FORWARD 20
RIGHT 90
ENDREPEAT
7
8
9
10
FORWARD 20
LEFT 90
FORWARD 20
LEFT 90
1 mark
1 mark
11 FORWARD 20
12 RIGHT 90
13 FORWARD 20
1 mark
14 RIGHT 90
15 FORWARD 20
16 PENUP
1 mark
17
18
19
20
FORWARD 20
PENDOWN
FORWARD 20
RIGHT 90
21 FORWARD 60
22 RIGHT 90
23 FORWARD 20
[NOTE: –
–
–
[4]
1 mark
1 mark
award 1 mark for each correct block (shown separated by dotted lines)
look out for alternative solutions using REPEAT/ENDREPEAT which may be correct
if a mistake in one of the blocks, start marking from the end awarding marks for
correct blocks up to the error]
[6]
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Page 7
10 (a)
Syllabus
7010
Paper
12
START
No
any more
barcodes
to scan ?
Yes
9
scan barcode
(1 mark)
STOP
No
2
5
Yes
(1 mark)
11
(1 mark)
(1 mark)
No
1
7
Yes
6
(1 mark)
10
(1 mark)
Yes
4
(1 mark)
No
12
3
(1 mark)
No
Yes
8
[8]
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Page 8
Syllabus
7010
Paper
12
(b) 1 mark for each device + 1 mark for correct matching use
device:
use:
beeper/loud speaker
to indicate barcode correctly read/error in reading barcode
device:
use:
(LCD) screen/monitor
to show prices and other information about goods
device:
use:
touch screen
to show prices and other information about goods/to select items that need to be
weighed/identified
device:
use:
weighing machine
to find weight of loose items (e.g. fruit) to enable pricing
device:
use:
(magnetic) card reader/CHIP and PIN reader
to read customer’s debit/credit card/enable customer to pay for goods using a
credit or debit card
device:
use:
printer
to print receipts
(NOT keypad)
[4]
11 (a) = (B2/24) * B3
[1]
(b) = C4 * B5
[1]
(c) = IF (D1 < C6, “profit”, “no profit”) (NOTE: accept C6 > D1 in formula)
1 mark 1 mark
[2]
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Cambridge O Level – October/November 2014
Page 9
(d)
A
B
Syllabus
7010
C
D
1
1500
2
18
3
60
4
5
Paper
12
45
40
6
1800
1 mark
profit
1 mark
1 mark
[3]
12 (a) 1 mark for each of four rows shown in bold below; there are two possible ways of doing this –
one set of answers is shown on the left and the alternative is shown on the right in brackets.
Don’t allow mix and match; answers must either be as shown on the left OR as shown on the
right
0 0 0 0 0 0
0 0 1 0 0 1
(OR 0 0 1 1 0 1)
– 1 mark
0 0 0 0 0 1
(OR 0 0 0 1 0 1)
– 1 mark
0 0 1 1 0 1
(OR 0 0 1 1 0 0)
– 1 mark
0 0 0 1 0 1
(OR 0 0 0 1 0 0)
– 1 mark
0 0 0 0 0 0
0 0 0 0 0 0
0 0 0 0 0 0
[4]
(b) 2 marks for identifying the letter
letter: H
[2]
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Page 10
Syllabus
7010
Paper
12
13 (a)
A
B
C
X
0
0
0
0
0
0
1
0
0
1
0
1
0
1
1
1
1
0
0
1
1
0
1
1
1
1
0
1
1
1
1
1
1 mark
1 mark
1 mark
1 mark
[4]
(b) 1 mark per correct NOR gate and NAND gate on the left (ONLY accept two-input gates)
A
1 mark
X
B
1 mark
C
[2]
(c) 1 mark per logic statement as shown below:
(A = 1 AND B = 1) OR (B = NOT 1 AND C = 1)
(1 mark)
(1 mark)
(1 mark)
The above can be written as:
(A AND B) OR (NOT B AND C)
(1 mark) (1 mark) (1 mark)
Note: allow 1st part of formula and 2nd part of formula to be reversed:
(e.g. (NOT B AND C) OR (A AND B))
Also accept Boolean algebra:
b .c
a.b
+
(1 mark) (1 mark) (1 mark)
(can be written as: A.B + B.C)
[3]
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Page 11
Syllabus
7010
Paper
12
14 NOTE: sum1, sum2 and total MUST be initialised for all three inputs to get the mark; allow
repetition in any of the columns EXCEPT the OUTPUT column (e.g. sum1 can be 0, 47, 47, 47,
47, 47, 47);
sum1
sum2
total
a
b
c
d
e
f
0
0
0
4
3
2
0
0
8
47
8
55
OUTPUT
44
33
22
11
0
0
0
0
34
16
50
data are
OK
5
0
1
2
3
4
39
28
17
6
-5
error
0
0
0
0
0
0
0
0
0
1 mark
1 mark
1 mark < - - - - - - - - - - - - - - - - - 1 mark - - - - - - - - - - - - - - - >
1 mark
[5]
15 1 mark per feature applied to text in question:
taxi
cabs
– search and replace feature/retype/thesaurus
yelow
yellow
– spell checker/retype/auto-correct
changed
replaced
– search and replace feature/retype/thesaurus
translate last sentence/line
– (auto-)translator English to Spanish/other language
[4]
© Cambridge International Examinations 2014
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Mark Scheme
Cambridge O Level – October/November 2014
Syllabus
7010
Paper
12
16 marking points:
•
•
•
•
•
•
•
•
initialise highest value (zero or less)
loop control for all 3000 students
set total = 0 (to find the average) before second loop
loop control for all 8 exams
check if input mark higher than stored highest mark
if input mark higher, then set highest to this new value
find the average mark for each student (includes correct total addition)
both outputs in the correct place
(average after inside loop, highest outside outer loop)
(must be an attempt to find both average and highest to earn this mark)
sample program:
highest = -1
for student = 1 to 3000
total = 0
for exam = 1 to 8
input mark
total = total + mark
if mark > highest then highest = mark
next
average = total/8
output average
next
output highest
1 mark
1 mark
1 mark
1 mark
2 marks
1 mark
1 mark
[5]
© Cambridge International Examinations 2014
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Cambridge International Examinations
Cambridge Ordinary Level
* 4 5 1 3 7 5 4 9 8 7 *
7010/13
COMPUTER STUDIES
Paper 1
October/November 2014
2 hours 30 minutes
Candidates answer on the Question Paper.
No Additional Materials are required.
READ THESE INSTRUCTIONS FIRST
Write your Centre number, candidate number and name on all the work you hand in.
Write in dark blue or black pen.
You may use an HB pencil for any diagrams, graphs or rough working.
Do not use staples, paper clips, glue or correction fluid.
DO NOT WRITE IN ANY BARCODES.
Answer all questions.
No marks will be awarded for using brand names of software packages or hardware.
At the end of the examination, fasten all your work securely together.
The number of marks is given in brackets [ ] at the end of each question or part question.
This document consists of 22 printed pages and 2 blank pages.
DC (LK/CGW) 100855
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2
1
Give, with reasons, three safety issues associated with the use of computers in the office.
1 ......................................................................................................................................................
.........................................................................................................................................................
.........................................................................................................................................................
2 ......................................................................................................................................................
.........................................................................................................................................................
.........................................................................................................................................................
3 ......................................................................................................................................................
.........................................................................................................................................................
..................................................................................................................................................... [3]
2
In the diagram below, there are two types of memory shown on the left and five typical memory
features shown on the right.
Link each feature to either RAM or ROM by drawing connecting lines.
non-volatile memory
RAM
volatile memory
can be written to and read from
ROM
the contents cannot be changed
stores data or files the user is
currently working on
[5]
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3
3
(a) Felipe wrote down the following three statements.
In each case, indicate whether the statement is true or false and give a reason for your choice.
“encrypting data prevents it from being hacked”
TRUE/FALSE ............................................................................................................................
Reason .....................................................................................................................................
...................................................................................................................................................
...................................................................................................................................................
“backing up data removes the risk of the data being infected by viruses”
TRUE/FALSE ............................................................................................................................
Reason .....................................................................................................................................
...................................................................................................................................................
...................................................................................................................................................
“wireless (WiFi) networks are less secure than hard-wired systems”
TRUE/FALSE ............................................................................................................................
Reason .....................................................................................................................................
...................................................................................................................................................
...............................................................................................................................................[3]
(b) Felipe uses Internet banking. When he logs on, the website asks for the 1st, 4th and 8th
characters in his password. He selects the characters from drop-down boxes.
(i)
State why drop-down boxes are used.
...........................................................................................................................................
.......................................................................................................................................[1]
(ii)
Felipe is also asked to confirm the last date and time when he logged onto the website.
State why he is asked to confirm this.
...........................................................................................................................................
.......................................................................................................................................[1]
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4
(iii)
When Felipe wishes to return to a previous page on this website, he clicks on the
View My Account option rather than using the browser arrows. If he uses the browser
arrows, he is logged out of the website.
Give a reason why the website does this.
...........................................................................................................................................
...........................................................................................................................................
.......................................................................................................................................[1]
4
Rikki uses an expert system, installed on her laptop computer, to trace faults in television sets.
She visits a customer and tries to locate the problem using the expert system.
(a) Explain how Rikki and the expert system will interact to help diagnose the fault in the television.
...................................................................................................................................................
...................................................................................................................................................
...................................................................................................................................................
...................................................................................................................................................
...................................................................................................................................................
...................................................................................................................................................
...............................................................................................................................................[3]
(b) The expert system requires certain files to be stored on a memory stick (or USB flash drive)
that must be connected to the laptop for the software to work.
Give two possible reasons why these extra files are stored on the memory stick.
1 ................................................................................................................................................
...................................................................................................................................................
2 ................................................................................................................................................
...............................................................................................................................................[2]
(c) Give an example of the use of an expert system other than fault diagnosis.
...................................................................................................................................................
...............................................................................................................................................[1]
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5
5
Six statements and six values are shown below.
Each statement will generate one possible value.
Draw a line to link each statement to its correct value.
statement
value
number of possible binary input
combinations for a 2-input logic
gate circuit
0
output from the logic gate:
1
1
1
base 10 (denary) value of the
following binary number:
4
2
1
1
1
0
4
what is the output from the
algorithm:
y=1
for x = 1 to 4
y=y*x
next x
print y
6
number of bytes formed from
8 bits
20
If there are 2X bytes in a Mbyte,
what is the value of X?
24
[5]
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6
6
The following pseudocode algorithm should:
• input up to 20 numbers
• stop if the sum of the input numbers exceeds 50
• output the final sum
10
20
30
40
50
60
70
80
count = 0
REPEAT
INPUT n
n + sum = sum
IF sum = 50 THEN count = 20
count = count + 1
UNTIL count = 20
OUTPUT n
There are five errors in this algorithm.
Locate these errors and suggest a correction.
error 1 .......................................................................................................................................
correction ..................................................................................................................................
...................................................................................................................................................
error 2 .......................................................................................................................................
correction ..................................................................................................................................
...................................................................................................................................................
error 3 .......................................................................................................................................
correction ..................................................................................................................................
...................................................................................................................................................
error 4 .......................................................................................................................................
correction ..................................................................................................................................
...................................................................................................................................................
error 5 .......................................................................................................................................
correction ..................................................................................................................................
...............................................................................................................................................[5]
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7
7
The following five statements about the Internet are incomplete:
(i)
< - - - - (a) - - - - > includes software that allows users to create and edit web pages using a
browser. Anyone is able to create or edit this information.
(ii)
< - - - - (b) - - - - > allow interaction of people online. Users can add friends, post messages
and update their personal profiles to notify friends about their status.
(iii)
A series of digital media files that are released at regular intervals and downloaded to the
user’s computer are known as < - - - - (c) - - - - >. These media files are stored and maintained
centrally.
(iv)
< - - - - (d) - - - - > is a type of bookmarking where a user “marks” a webpage or photo
using text to describe its contents. Anyone can view the webpages or photos corresponding
to these “markers”.
(v)
Internet journals where a writer enters text about a particular topic or person are known as
< - - - - (e) - - - - >.
Complete the five statements above using terms from the following list:
•
•
•
•
•
•
•
•
blogs
data (bit) streaming
Internet service provider
podcasts
social networking sites
tagging
web browser
wikis
(a) .................................................................................................................................................[1]
(b) .................................................................................................................................................[1]
(c) .................................................................................................................................................[1]
(d) .................................................................................................................................................[1]
(e) .................................................................................................................................................[1]
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8
8
Data sent across the Internet are frequently encrypted. The following flowchart shows a basic
encryption method (Note: the → symbol in the flowchart means “is replaced by”).
START
INPUT
character
is character =
“.” ?
Yes
STOP
No
is character a
vowel ?
Yes
a
e
i
o
u
A
A
A
A
A
o
u
a
e
i
b
c
d
f
g
h
j
A
A
A
A
A
A
A
s
t
v
w
x
y
z
k
l
m
n
p
q
r
A
A
A
A
A
A
A
b
c
d
f
g
h
j
s
t
v
w
x
y
z
A
A
A
A
A
A
A
k
l
m
n
p
q
r
No
is character =
b,c,d,f,g,h or j ?
Yes
No
is character =
k,l,m,n,p,q or r ?
Yes
No
No
© UCLES 2014
is character =
s,t,v,w,x,y or z ?
Yes
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9
For example,
l o
i
a m
a
r o b o t
.
y u c c e
a
o d
o
j e s e l
.
h e l
becomes:
(a) Use the flowchart to encrypt the following message:
m e e t
i n g
w i
l
l
g o
a h e a d .
[2]
(b) Use the information in the flowchart to show which input message produced the following
encrypted message:
t e d g i
l a f x
a k
w i
f
.
[2]
(c) Many customers shop online.
Apart from encryption, describe three other security features built into many online shopping
websites.
1 ................................................................................................................................................
...................................................................................................................................................
2 ................................................................................................................................................
...................................................................................................................................................
3 ................................................................................................................................................
...............................................................................................................................................[3]
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10
9
A cinema (movie theatre) uses automatic machines to allow customers to select tickets for movie
shows. Payments are made by credit or debit card.
(a) Identify two input devices which could be used by the cinema.
For each device, describe what it is used for.
input device 1 ............................................................................................................................
use ............................................................................................................................................
...................................................................................................................................................
...................................................................................................................................................
input device 2 ............................................................................................................................
use ............................................................................................................................................
...................................................................................................................................................
...............................................................................................................................................[4]
(b) Identify two output devices which could be used by the cinema.
For each device, describe what it is used for.
output device 1 ……………………………………………………………………………………
use ............................................................................................................................................
...................................................................................................................................................
...................................................................................................................................................
output device 2 .........................................................................................................................
use ............................................................................................................................................
...................................................................................................................................................
...............................................................................................................................................[4]
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11
10 A microwave oven cooks food when the food is placed on a rotating plate and the door is closed.
The oven is controlled by a microprocessor.
(a) Name two sensors that could be used in the microwave oven.
1 ................................................................................................................................................
2 ............................................................................................................................................[2]
(b) Describe two items of data that the user would need to input before pressing the start button.
Describe how these data could be input.
data 1
...................................................................................................................................................
...................................................................................................................................................
method of input 1
...................................................................................................................................................
...................................................................................................................................................
data 2
...................................................................................................................................................
...................................................................................................................................................
method of input 2
...................................................................................................................................................
.............................................................................................................................................. [4]
(c) Describe the role of the microprocessor in the microwave oven.
...................................................................................................................................................
...................................................................................................................................................
...................................................................................................................................................
...................................................................................................................................................
...................................................................................................................................................
...................................................................................................................................................
.............................................................................................................................................. [4]
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12
11 An algorithm has been written to input six temperatures for every day of the year (365 days). The
outputs are:
• the average daily temperature for each day
• the highest recorded temperature for the whole year
The algorithm is in the form of a flowchart on the next page. However, several of the statements
are missing.
Using instruction number only, complete the flowchart using the following list of instructions:
Instruction
number
© UCLES 2014
Instruction
1
average = total / 6
2
day = day + 1
3
high = -200
4
high = temperature
5
input temperature
6
is reading <= 6 ?
7
is temperature > high ?
8
output average
9
output high
10
reading = reading + 1
11
total = 0
12
total = total + temperature
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START
day = 1
reading = 1
Yes
No
Yes
No
STOP
Yes
is day <=
365 ?
No
[6]
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14
12 A spreadsheet has been set up to allow a motorist to keep a check on his fuel costs.
A
B
C
D
1
2
input number of
litres of fuel used
3
input number of km
driven
4
calculated fuel
consumption
5
input number of km
driven each year
6
calculated annual
fuel cost
Data are input into cells B2, B3 and B5 and results appear in cells C4 and C6.
(a) (i)
Fuel consumption is calculated as kilometres per litre.
Give the formula you would expect to see in C4.
= ........................................................................................................................................
(ii)
Assume that fuel costs $2.00 per litre.
Give the formula you would expect to see in cell C6.
= ....................................................................................................................................[2]
(b) It was decided to include an extra input in D1. The value input is the motorist’s fuel allowance
(in $) for the year.
Cell D6 will show whether the calculated annual fuel cost is above the annual fuel allowance
or not.
Complete the following formula which must be in D6:
= IF (…………….……….………….….., " …………….…………………. ", "equal or below")
[2]
(c) Identify which cells would be automatically updated if the value in cell B3 was changed.
...................................................................................................................................................
...............................................................................................................................................[1]
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16
13 Study the following flowchart very carefully.
START
T1 = 0
T2 = 0
T3 = 0
INPUT A, B, C
is A = 0
and B = 0 and
C=0?
Yes
OUTPUT T1,
T2, T3
STOP
No
is A > B ?
Yes
No
is B > C ?
is A > C ?
Yes
T1 = T1 + 1
No
No
T3 = T3 + 1
Yes
T2 = T2 + 1
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17
(a) Complete the trace table for the flowchart using the following data:
3, 2, 1
T1
4, 8, 7
T2
6, 0, 3
T3
5, 6, 9
A
4, 11, 3
B
0, 0, 0
C
OUTPUT
[5]
(b) This flowchart does not give correct answers for certain sets of test data.
Suggest a data set that would give an incorrect answer.
Give a reason for your choice.
data set .....................................................................................................................................
...................................................................................................................................................
reason .......................................................................................................................................
...................................................................................................................................................
...............................................................................................................................................[2]
© UCLES 2014
7010/13/O/N/14
M.Mushtaq
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18
14 Digits on an electronic display board can be represented on a 7 × 5 grid. For example, the digit 3 is
represented as:
1 2 3 4 5
Row 1
Row 2
Row 3
Row 4
Row 5
Row 6
Row 7
Each column in the grid is represented in a computer as a 7-bit register. Five registers are required
to represent the state of the whole digit. The value 1 represents a shaded square and the value 0
represents an unshaded square. For example, the digit 3 is represented as:
Row number: 1 2 3 4 5 6 7
Register 1
Register 2
Register 3
Register 4
Register 5
0
1
1
1
0
1
0
0
0
1
0
0
0
0
1
0
0
1
1
0
0
0
0
0
1
1
0
0
0
1
0
1
1
1
0
(a) Show the contents of the five 7-bit registers when representing the digit 9:
1 2 3 4 5
1
2
3
4
5
6
7
Row number:
1
2
3
4
5
6
7
Reg 1
Reg 2
Reg 3
Reg 4
Reg 5
[4]
© UCLES 2014
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19
(b) In order to prevent errors, an 8-bit register is used. The 8th bit will contain:
• 0 – if the first 7 bits add up to an even number
• 1 – if the first 7 bits add up to an odd number
Complete the 8th bit for each register. The first register has been completed for you.
1
2
3
4
5
6
7
8
Reg 1
0
1
0
0
0
1
0
0
Reg 2
1
0
0
0
0
0
1
Reg 3
1
0
0
1
0
0
1
Reg 4
1
0
0
1
0
0
1
Reg 5
0
1
1
0
1
1
0
[3]
© UCLES 2014
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20
15 (a) Complete the truth table for the following logic circuit:
A
B
X
C
A
B
C
0
0
0
0
0
1
0
1
0
0
1
1
1
0
0
1
0
1
1
1
0
1
1
1
Working
X
[4]
© UCLES 2014
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21
(b) Re-draw the logic circuit shown opposite, using NAND and NOR gates only.
[2]
(c) Write a logic statement that describes the following logic circuit:
A
B
X
C
...................................................................................................................................................
...................................................................................................................................................
...................................................................................................................................................
...................................................................................................................................................
...............................................................................................................................................[3]
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22
16 A customer wants to compare prices of 1000 items sold in two supermarkets (price1 and price2).
Write an algorithm, using pseudocode or a flowchart, which:
•
•
•
•
inputs the two prices for all 1000 items
outputs how many items were more expensive in supermarket 1
outputs how many items were more expensive in supermarket 2
outputs the largest price difference
..........................................................................................................................................................
..........................................................................................................................................................
..........................................................................................................................................................
..........................................................................................................................................................
..........................................................................................................................................................
..........................................................................................................................................................
..........................................................................................................................................................
..........................................................................................................................................................
..........................................................................................................................................................
..........................................................................................................................................................
..........................................................................................................................................................
..........................................................................................................................................................
..........................................................................................................................................................
..........................................................................................................................................................
..........................................................................................................................................................
..........................................................................................................................................................
..........................................................................................................................................................
..........................................................................................................................................................
..........................................................................................................................................................
..........................................................................................................................................................
..........................................................................................................................................................
......................................................................................................................................................[6]
© UCLES 2014
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639
CAMBRIDGE INTERNATIONAL EXAMINATIONS
Cambridge Ordinary Level
MARK SCHEME for the October/November 2014 series
7010 COMPUTER STUDIES
7010/13
Paper 1, maximum raw mark 100
This mark scheme is published as an aid to teachers and candidates, to indicate the requirements of
the examination. It shows the basis on which Examiners were instructed to award marks. It does not
indicate the details of the discussions that took place at an Examiners’ meeting before marking began,
which would have considered the acceptability of alternative answers.
Mark schemes should be read in conjunction with the question paper and the Principal Examiner
Report for Teachers.
Cambridge will not enter into discussions about these mark schemes.
Cambridge is publishing the mark schemes for the October/November 2014 series for
most Cambridge IGCSE®, Cambridge International A and AS Level components and some
Cambridge O Level components.
® IGCSE is the registered trademark of Cambridge International Examinations.
M.Mushtaq
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Mark Scheme
Cambridge O Level – October/November 2014
Page 2
1
Syllabus
7010
Paper
13
Any three from (need risk + reason):
Safety issues e.g.:
–
–
–
–
electrocution from bare wires or spilling liquids on live equipment
trip hazard due to trailing wires
risk of heavy equipment falling from inadequate desks
risk of fire if insufficient equipment ventilation or overloaded wall sockets
[3]
2
non-volatile memory
volatile memory
RAM
can be written to and read
from
the contents cannot be
changed
ROM
stores data or files the user
is currently working on
1 mark for each correct line (max 5)
Deduct 1 mark for each additional incorrect line.
[5]
3
(a) FALSE
– encryption only stops data being read / making sense (but does not prevent
the act of hacking)
FALSE
– data when backed up could still have the virus attached to it
– when the backed up data is re-loaded at a later date, the virus could be
loaded again into the system together with the stored data
TRUE
– tapping into a Wi-Fi network is relatively easy (even when the network is
protected by passwords)
1 mark for each correct TRUE / FALSE with correct corresponding reason
[3]
© Cambridge International Examinations 2014
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Mark Scheme
Cambridge O Level – October/November 2014
Page 3
Syllabus
7010
Paper
13
(b) (i) drop down boxes help defeat spyware / key logging software
[1]
(ii) – to ensure that it was in fact Felipe who logged on last time
– an additional authentication check
[1]
(iii) in case it is not Felipe who attempts to access the account
[1]
4
(a) Any three from:
– Expert System asks questions
– Rikki inputs the answers to the questions
– next question asked is based on previous response(s)
– search Knowledge Base ……
– ….. uses the Rules Base to draw conclusions
– use of Inference Engine
– probable faults / solutions output on a screen
– … and the % probability of accuracy is also given
[3]
(b) Any two from:
– security purposes as these files are needed to access the Expert System
– licence agreement to only allow an authorised number of computers to access Expert
System
– the extra files need to be accessed for the Expert System to work
[2]
(c) Any one from:
–
–
–
–
–
–
–
chess games
oil / mineral prospecting
tax calculations
weather forecasting
identify plants / animals/chemical compounds
careers guidance
car engine tuning
[1]
© Cambridge International Examinations 2014
M.Mushtaq
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Mark Sch
S heme
Cam
mbrridge
e O Level – Oct
O tober/N
Nov
vem
mber 20
014
4
Pag
P ge 4
Sylllabus
7 10
70
Pape
er
13
5
num
n
mbe
er of
o poss
p sible b
binary
y inputt
c mbin
com
nattion
ns for
f a2
2-inputt lo
ogic
c
g e ciircu
gate
uit
0
o put fro
outp
om the
e lo
ogicc ga
ate:
1
1
1
base 10 (de
b
( nary) va
alue
e off the
fo
ollo
owing bin
nary
y num
n mbe
er:
4
2
1
1
1
0
4
wha
w
at iss th
he out
o tputt fro
om the
a orith
algo
hm
m:
y=1
fo
or x = 1 to
t 4
y=y*x
next x
p nt y
prin
6
n mbe
num
er of
o byte
b es form
f med frrom
m 8 bits
20
0
Iff there
e arre 2
x
by
yte
es in
n a Mbytte,
24
4
w at iss th
wha
he valu
v ue of x?
1 mar
m rk for ea
ach
h co
orrect line (m
max 5)
[5]
© Ca
amb
bridge
e In
nterrnational Ex
xam
minations
s 20
014
4
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Mark Scheme
Cambridge O Level – October/November 2014
Page 5
6
Syllabus
7010
Paper
13
1 mark for each error located with corresponding correction (description or corrected pseudocode
acceptable)
error:
correction:
line 10: sum not initialised
sum = 0
error:
correction:
line 40: incorrect formula for sum
sum = sum + n
error:
correction:
line 50: incorrect IF statement
IF sum > 50 THEN ……
error:
correction:
lines 50 and 60: value of count causes a problem e.g. loop never ending
either count = 19 on line 50
or
count = count + 1 between lines 30 and 40
or
any other correct solution
error:
correction
line 80: output of n is incorrect
output sum or print sum
[5]
7
(a) wikis
[1]
(b) social networking sites
[1]
(c) podcasts
[1]
(d) tagging
[1]
(e) blogs
[1]
8
(a)
duul a f x
na c c
< - - - - - - - - - - - - - - 1 mark - - - - - - - - - - - - - ->
x e
oy uov .
<- - - - - - - - - - 1 mark - - - - - - - - ->
[2]
(b)
c o m p u t i n g
<- - - - - - - - - - - - - 1 mark - - - - - - - - - - - - ->
i s
f u n .
<- - - - - - - - - 1 mark - - - - - - - - ->
[2]
© Cambridge International Examinations 2014
M.Mushtaq
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Mark Scheme
Cambridge O Level – October/November 2014
Page 6
Syllabus
7010
Paper
13
(c) Any three from:
–
–
–
–
–
–
–
–
–
–
–
customers need a password / PIN
use of card readers / use of Transaction Authentication Number (TAN)
only certain characters from password / PIN requested…
…the requested characters change each time user logs on
card security code requested
use of drop down boxes
use of a customer reference number
inform customer when they last logged on to the website
use of image verification code e.g. CAPTCHA
make reference to something unique to the customer e.g. their mobile phone number
use of secure protocol e.g. https, padlock symbol
[3]
9
(a) 1 mark for input device + 1 mark for its matching use
input device:
use:
touch screen
select film / cinema seats / price
input device:
use:
keyboard / keypad
input number of tickets / card PIN
input device:
use:
magnetic stripe reader / chip and PIN reader / card reader
reading credit / debit card details
input device:
use:
scanner
to read any promotional vouchers (etc.)
[4]
(b) 1 mark for each different output device + 1 mark for its matching use
output device: screen / monitor
use:
show films available / seating plan / prices of each seat / payment details
output device: printer
use:
print receipt / tickets
output device: loudspeaker / beeper
use:
to indicate error in input / confirmation of keys pressed
[4]
10 (a) 1 mark for each different sensor (max 2)
– pressure sensor
– example of sensor to detect if door closed / open e.g. magnetic field sensor, proximity
sensor
– moisture / humidity sensor
– temperature / infrared sensor
[2]
© Cambridge International Examinations 2014
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Mark Scheme
Cambridge O Level – October/November 2014
Page 7
Syllabus
7010
Paper
13
(b) 1 mark for each item of data (max 2):
–
–
–
–
–
–
–
is the food frozen / uncooked / cooked?
cooking time
start / end time
power
weight
type of food
additional cooking feature e.g. browning
1 mark for each corresponding input method (max 2):
– turn dial to select option
– touch screen / buttons / concept keyboard / keypad to select options
– use of barcode readers (to read barcodes on food packaging which stores an automatic
cooking programme)
[4]
(c) Any four from:
– (microprocessor) checks / receives readings / data / signals from sensors….
– …..continuously
– if door open, (microprocessor) sends signal to sound alarm / stop process
– (microprocessor) compares weight of food against stored values…
– …and automatically sets cooking time / power
– cooking time controlled by (microprocessor) comparing with stored values
– (microprocessor) sends signal to beeper / notify when cooking program complete
[4]
© Cambridge International Examinations 2014
M.Mushtaq
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Page 8
646
Mark Scheme
Cambridge O Level – October/November 2014
Syllabus
7010
Paper
13
11
START
3
day = 1
11
(1 mark)
reading = 1
5
(1 mark)
Yes
4
7
No
10/12
(1 mark)
12/10
Yes
6
1
No
(1 mark)
1
8
(1 mark)
2
Yes
STOP
No
is days
<= 365 ?
9
(1 mark)
[6]
1
© Cambridge International Examinations 2014
M.Mushtaq
03215275281
647
Mark Scheme
Cambridge O Level – October/November 2014
Page 9
12 (a) (i) B3 / B2
Syllabus
7010
Paper
13
(1 mark)
(ii) (B5 / C4) * 2 or = ((B5 * B2) / B3) * 2
(1 mark)
[2]
(b) = IF(C6>D1, “above”, “equal or below”)
1 mark 1 mark
OR
= IF(D1<C6, “above”, “equal or below”)
1 mark 1 mark
Alternative word(s) for “above” are acceptable.
[2]
(c) C4, C6, D6
[1]
© Cambridge International Examinations 2014
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Mark Scheme
Cambridge O Level – October/November 2014
Page 10
Syllabus
7010
Paper
13
13 (a)
T1
T2
T3
0
0
0
A
B
C
3
2
1
4
8
7
6
0
3
5
6
9
4
11
3
0
0
0
OUTPUT
1
1
2
1
2
2, 2, 1
1 mark
1 mark
1 mark
< - - - - - - - - - - 1 mark - - - - - - - - - - - ->
1 mark
If no marks are awarded for the columns then 1 mark can be given for correct initialisation of
T1, T2 & T3 as shown in the first row above.
[5]
(b) – any data set (except 0, 0, 0) where 2/3 of the numbers are the same e.g. 2, 8, 8
– flowchart does not allow for numbers which have the same value
[2]
© Cambridge International Examinations 2014
M.Mushtaq
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Mark Scheme
Cambridge O Level – October/November 2014
Page 11
14 (a) Row number:
Syllabus
7010
1
2
3
4
5
6
7
Reg 1:
0
1
1
0
0
0
0
Reg 2:
1
0
0
1
0
0
1
Reg 3:
1
0
0
1
0
1
0
Reg 4:
1
0
0
1
1
0
0
Reg 5:
0
1
1
0
0
0
0
Paper
13
Reg 1 + Reg 5 = 1 mark
Reg 2 = 1 mark
Reg 3 = 1 mark
Reg 4 = 1 mark
[4]
(b)
8
Reg 1:
0
Reg 2:
0
Reg 3:
1
Reg 4:
1
Reg 5:
0
Reg 2 + Reg 5 = 1 mark
Reg 3 = 1 mark
Reg 4 = 1 mark
[3]
© Cambridge International Examinations 2014
M.Mushtaq
03215275281
650
Mark Sch
S heme
Cam
mbrridge
e O Level – Oct
O tober/N
Nov
vem
mber 20
014
4
Pag
ge 12
1
Sylllabus
S
7 10
70
Pape
P
er
13
15
5 (a)
(
A
B
C
X
0
0
0
0
0
0
1
0
0
1
0
0
0
1
1
1
1
0
0
0
1
0
1
0
1
1
0
0
1
1
1
1
1 mark
1 mark
[4]
1 mark
1 mark
[4]
( ) 1 marrk for
(b)
f corre
ect NO
OR
R ga
ate and 1 ma
ark for corr
c rec
ct NAND
D gate
e in corrrect positio
ons
s on
n le
eft
h nd sid
han
s de of
o dia
d agra
am
m.
A
X
B
C
[2]
[ A = NO
(
(c)
NOT 1 OR
R B = NOT
N T1]
A D
AN
[ B = 1 AN
AND C = NO
OT 1 ]
1 ma
m rk
1 ma
m rk
1 ma
m rk
O her no
Oth
otations wh
hic
ch are
a e accepttab
ble:
(NO
OT A OR
R NO
N T B)
B AN
AND (B AND
D NOT
N T C)
_ _
_
(A
A + B)
B . (B
B . C)
C
(A
A' + B')
B . (B . C')
[3]
© Ca
amb
bridge
e In
nterrnational Ex
xam
minations
s 20
014
4
M.Mushtaq
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651
Mark Scheme
Cambridge O Level – October/November 2014
Syllabus
7010
Paper
13
16 Marking points:
•
•
•
•
•
•
•
•
initialise largest and two totals
control loop for 1000 items
check if price 1 > price 2 and increment total 1 (inside loop)
check if price 2 > price 1 and increment total 2 (inside loop)
calculate price difference (inside loop)
method of dealing with negative difference
check if calculated difference > largest difference and action taken if it is
three outputs OUTSIDE a loop (calculation must have been attempted)
Sample program in pseudocode:
largest = 0
smarket1 = 0: smarket2 = 0
for item = 1 to 1000
input price1, price2
if price1 > price2 then smarket1 = smarket1 + 1
if price2 > price1 then smarket2 = smarket2 + 1
difference = price1 – price2
if difference < 0 then difference = - difference
if difference > largest then largest = difference
next item
output smarket1, smarket2, largest
1 mark
1 mark
1 mark
1 mark
1 mark
1 mark
1 mark
1 mark
(max 6)
[6]
© Cambridge International Examinations 2014
M.Mushtaq
03215275281
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Cambridge International Examinations
Cambridge Ordinary Level
COMPUTER SCIENCE
2210/01
For Examination from 2015
Paper 1 Theory
SPECIMEN PAPER
1 hour 45 minutes
Candidates answer on the Question Paper.
No Additional Materials are required.
READ THESE INSTRUCTIONS FIRST
Write your Centre number, candidate number and name in the spaces at the top of this page.
Write in dark blue or black pen.
You may use an HB pencil for any diagrams, graphs or rough working.
Do not use staples, paper clips, glue or correction fluid.
Calculators must not be used in this paper.
Answer all questions.
No marks will be awarded for using brand names of software packages or hardware.
At the end of the examination, fasten all your work securely together.
The number of marks is given in brackets [ ] at the end of each question or part question.
This document consists of 14 printed pages.
[Turn over
© UCLES 2012
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2
1
A company selling CDs uses a unique 6-digit identification number for each CD title. The rightmost digit (position 1) is a check digit.
For example,
digit position
identification number
6 5 4 3 2 1
3 0 6 1 4 9
check digit
The validity of the number and check digit is calculated as follows:
•
•
•
•
multiply each digit by its digit position
add up the results of the multiplications
divide the answer by 11
if the remainder is 0, the identification number and check digit are valid.
(a) Show whether the following identification numbers are valid or not. You must show how you
arrived at your answer.
Identification number 1: 4 2 1 9 2 3
working:
valid or not valid?
Identification number 2: 8 2 0 1 5 6
working:
valid or not valid?
© UCLES 2012
[3]
2210/01/SP/15
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3
(b) Find the check digit for this identification number.
5 0 2 4 1
working:
check digit:
[2]
(c) Describe, with examples, two different types of data entry errors that a check digit would
detect.
1
2
[2]
2
Kamil is setting up a new computer system to record television programmes. He wants to be able
to record, view and then erase programmes that he does not want to keep. He has chosen to use
DVD-RAM as an optical storage medium.
Explain to Kamil why it is better to use DVD-RAM rather than DVD+RW or DVD-RW.
1
2
[2]
© UCLES 2012
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4
3
An alarm, Y, sends a signal (Y = 1) when certain fault conditions in a chemical process are
detected. The inputs are:
Input
Binary value
Condition
1
acidity > 5
0
acidity <= 5
1
temperature >= 120UC
0
temperature < 120UC
1
stirrer bar ON
0
stirrer bar OFF
A
T
S
The alarm, Y, returns a value of 1 if:
either
temperature >= 120UC AND stirrer bar is OFF
or
acidity > 5 AND temperature < 120UC
(a) Draw the logic circuit for the above system using these logic gates.
NOT
AND
OR
A
Y
T
S
[5]
© UCLES 2012
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5
(b) Complete the truth table for this alarm system.
A
T
S
0
0
0
0
0
1
0
1
0
0
1
1
1
0
0
1
0
1
1
1
0
1
1
1
Y
[4]
© UCLES 2012
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6
4
A digital alarm clock is controlled by a microprocessor. It uses the 24-hour clock system (i.e. 6 pm
is 18:00).
Each digit in a typical display is represented by a 4-digit binary code.
For example:
0
0
0
0
1st digit (0)
1
0
0
0
2nd digit (8)
0
0
1
1
3rd digit (3)
0
1
0
1
4th digit (5)
is represented by:
(clock display)
(a) What time is shown on the clock display if the 4-digit binary codes are:
0
0
0
1
0
1
1
0
0
1
0
0
1
0
0
1
(clock display)
[2]
(b) What would be stored in the 4-digit binary codes if the clock display time was:
1st digit
2nd digit
3rd digit
4th digit
[4]
© UCLES 2012
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7
(c) The clock alarm has been set at 08:00.
Describe the actions of the microprocessor which enable the alarm to sound at 08:00.
[2]
5
Bytes of data transferred using a serial cable are checked for errors at the receiving end using an
even parity check.
Can these bytes of data pass the even parity check?
(a) 01010101
[1]
(b) 11001000
[1]
(c) How can any errors be corrected?
[2]
© UCLES 2012
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8
6
The conditions in a fish tank are being controlled using sensors and a microprocessor. To keep
the fish healthy, the temperature must be at 25°C and the oxygen content needs to be 20 ppm
(parts per million). The tank contains a heater and an oxygen inlet controlled by a valve.
heater
oxygen supply
sensor A
sensor B
microprocessor
(a) Name the two sensors used in this application.
Sensor A
Sensor B
[2]
(b) Describe how the sensors and the microprocessor are used to maintain the correct
conditions in the fish tank.
[4]
(c) What safeguards are needed to stop the fish tank temperature rising too high?
[1]
© UCLES 2012
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9
7
Ahmed uses the Internet for some time and is puzzled by the terminology.
(a) Draw a line to match each description to the appropriate technical term.
authoring language used to
create documents to be viewed
on the World Wide Web
Browser
computer that responds to
requests to provide information
and services over the Internet
HTML
defines how messages are
transmitted and formatted
over the Internet
MAC address
numerical ID for each device
on the Internet
Internet Server
software that enables users
to access/view documents and
other resources on the Internet
IP address
unique ID for a network
interface card
http
[5]
(b) Ahmed sees the message “Set your browser to accept cookies”.
Explain why some websites make this request.
[2]
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8
Computer memories are measured in terms of the number of bytes.
(a) (i) What is meant by the term byte?
[1]
(ii) What is meant by the term Gigabyte?
[1]
(b) Flash memories and CD-RWs are used as backing media for computers.
Give two differences between these two media.
1
2
[2]
9
Andrew sends a large document to a printer.
(a) State the name for the area of memory used to store temporarily the data being sent to the
printer.
[1]
(b) The printer runs out of paper during the printing job. A signal is sent back to the computer to
stop temporarily its current task.
Name this type of signal.
[1]
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11
10 In a simple symmetric encryption system, each letter of the alphabet is substituted with another.
The plain text message:
The quick brown fox jumps over the lazy dog.
becomes the cypher text message:
Zag towns jumpy dmh coilp mngu zag bfke qmx.
(a) (i) Decode this cypher text message.
Agbbm Pmubq
[2]
(ii) Convert these words to cypher text.
Computer Science
[2]
(b) Both the person who sends the message and the person who receives it need to know
what the substitution key is, and they need to keep this secret. A copy of the
substitution key has been sent using SSL transmission.
Explain why this keeps the copy of the key secret during transmission.
[2]
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11 Five security or data loss issues are shown on the left-hand side.
Five possible methods of data recovery or protection are shown on the right.
Draw a line to match each definition/description of Issues to the most appropriate Methods of
Data Recovery.
Issues
Methods of Data Recovery
data loss caused by hard disk
head crash
anti-spyware software
hacking into files and changing
or deleting data
anti-virus software
introduction of software that
self-replicates and can cause
data loss
back-up files
reading of illegally accessed
documents
encryption
software that logs/records all
key presses on your computer
without you knowing
passwords and a firewall
[4]
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13
12 Look at these two pieces of code:
A:
CLC
LDX
loop: LDA
ADC
STA
INX
CPX
BNE
#0
A,X
B,X
C,X
B: FOR Loop
INPUT
Sum =
PRINT
NEXT
= 1 TO 4
Number1, Number2
Number1 + Number2
Sum
#16
loop
(a) Which of these pieces of code is written in a high-level language?
[1]
(b) Give one benefit of writing code in a high-level language.
[1]
(c) Give one benefit of writing code in a low-level language.
[1]
(d) High-level languages can be compiled or interpreted.
Give two differences between a compiler and an interpreter.
1
2
[2]
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14
13 When a key is pressed on the keyboard, the computer stores the ASCII representation of the
character typed into main memory.
The ASCII representation for A is 65 (denary), for B is 66 (denary), etc.
There are two letters stored in the following memory locations:
Location 1
A
Location 2
C
(a) (i) Show the contents of Location 1 and Location 2 as binary.
Location 1
Location 2
[2]
(ii) Show the contents of Location 1 and Location 2 as hexadecimal.
Location 1
Location 2
[2]
(b) The following machine code instruction is stored in a location of main memory:
1
1
1
1
1
0
1
0
1
0
0
1
0
1
1
1
Convert this binary pattern into hexadecimal.
[4]
(c) Explain why a programmer would prefer to see the contents of the locations displayed as
hexadecimal rather than binary, when debugging his program that reads the key presses.
[2]
Permission to reproduce items where third party owned material protected by copyright is included has been sought and cleared where possible. Every
reasonable effort has been made by the publisher (UCLES) to trace copyright holders, but if any items requiring clearance have unwittingly been included, the
publisher will be pleased to make amends at the earliest possible opportunity.
Cambridge International Examinations is part of the Cambridge Assessment Group. Cambridge Assessment is the brand name of University of Cambridge Local
Examinations Syndicate (UCLES), which is itself a department of the University of Cambridge.
© UCLES 2012
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Cambridge International Examinations
Cambridge Ordinary Level
COMPUTER SCIENCE
2210/01
For Examination from 2015
Paper 1 Theory
SPECIMEN MARK SCHEME
1 hour 45 minutes
MAXIMUM MARK: 75
This document consists of 8 printed pages.
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2
1
(a) 1 mark for the correct working in BOTH parts
1 mark for valid
1 mark for not valid
Identification number 1: working
= (4 × 6) + (2 × 5) + (1 × 4) + (9 × 3) + (2 × 2) + (3 × 1)
= 24 + 10 + 4 + 27 + 4 + 3
= 72 ÷ 11
= 6 remainder 6
valid/not valid: NOT valid
Identification number 2: working
= (8 × 6) + (2 × 5) + (0 × 4) + (1 × 3) + (5 × 2) + (6 × 1)
= 48 + 10 + 0 + 3 + 10 + 6
= 77 ÷ 11
= 7 remainder 0
valid/not valid: VALID
[3]
(b) 1 mark for correct working + 1 mark for check digit
working
= (5 × 6) + (0 × 5) + (2 × 4) + (4 × 3) + (1 × 2)
= 30 + 0 + 8 + 12 + 2
= 52
need to add 3 to make the total 55 (i.e. exactly divisible by 11)
check digit: 3
[2]
(c) 1 mark for each description and example
2
–
–
2 digits transposed
(e.g. 280419 becomes 280149/two digits have been switched)
incorrect digit
(e.g. 280419 becomes 250419/one of the digits has been mistyped)
[2]
direct access because of concentric tracks
can read and write at the same time because it has a read/write head
[2]
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3
3
(a) 1 mark for each logic gate correctly connected
A
AND
NOT
Y
OR
T
AND
S
NOT
[5]
(b)
A
T
S
Y
0
0
0
0
0
0
1
0
0
1
0
1
0
1
1
0
1
0
0
1
1
0
1
1
1
1
0
1
1
1
1
0
}
]
]
]
]
1 mark
1 mark
1 mark
1 mark
[4]
4
(a) 1 mark for hours; 1 mark for minutes
1 6 : 4 9
1 mark 1 mark
[2]
(b) 1 mark for each digit
0
0
0
1
© UCLES 2012
0
1
0
0
0
1
1
0
1
1
0
1
1st digit
2nd digit
3rd digit
4th digit
[4]
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5
(c) Any two from:
– microprocessor compares present time with stored time
– if the values are the same
– sends signal to sound alarm
[2]
(a) Yes
[1]
(b) No
[1]
(c) –
–
6
re-reading the byte that was sent
request that the byte is resent
[2]
(a) Only answers:
– temperature (sensor)
– oxygen (sensor)
[2]
(b) Any four from:
– information from the sensors sent to microprocessor
– the ADC converts the analogue data into digital form
– if temperature < 25ºC OR temperature checked against stored value
– ...microprocessor sends signal to heater/actuator/valve...
– ...to switch on heater
– if oxygen level < 20 ppm OR oxygen level checked against stored value
– ...to open valve/oxygen supply
– use of DAC between microprocessor and devices
– sounds an alarm if system unable to respond
– continuously monitors sensor inputs
– any reference to feedback
[4]
(c) Any one from:
– unsafe limit stored in memory
– warning sound/signal if too high a value reached
– fail safe switch off in case of a malfunction
[1]
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5
7
(a)
authoring language used to
create documents to be viewed
on the World Wide Web
Browser
computer that responds to
requests to provide information
and services over the Internet
HTML
defines how messages are
transmitted and formatted
over the Internet
MAC address
numerical ID for each device
on the Internet
Internet Server
software that enables users
to access/view documents and
other resources on the Internet
IP address
unique ID for a network
interface card
http
5/6 matches – 5 marks
4 matches – 4 marks
3 matches – 3 marks
2 matches – 2 marks
1 match – 1 mark
[5]
(b) any two from:
– to enable logon information to be kept on his computer
– to provide pages customised for Ahmed the next time he logs on
– to implement shopping carts and one-click purchasing
– to be able to distinguish between new and repeat visitors to the website
© UCLES 2012
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8
(a) (i) Any one from:
– unit of data/memory
– 8 bits
– used to represent a character
[1]
(ii) Any one from:
– 230 bytes
– 1 073 741 824 bytes
– 1 048 576 kilobytes
– 1024 megabytes
[1]
(b) Any two from:
Flash memory
– solid state memory
– no formatting issues
– plugs directly into the USB port
– direct transfer of data
CD-RW
– optical media
– slower access speed/flash memory has faster access speed
– requires a separate drive
– data needs to be burnt/finalised/finished (before being used on another device)
9
[2]
(a) Any one from:
– buffer
– RAM
[1]
(b) –
[1]
interrupt
10 (a) 1 mark for each correct word
(i) Hello World
[2]
(ii) Nmilozgu Pnwgyng
[2]
(b) –
–
© UCLES 2012
use of Secure Socket Layer
the key itself is encrypted using strong encryption
[2]
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7
11
data loss caused by hard disk
head crash
anti-spyware software
hacking into files and changing or
deleting data
anti-virus software
introduction of software that
self-replicates and can cause
data loss
back-up files
reading of illegally accessed
documents
encryption
software that logs/records all
key presses on your computer
without you knowing
passwords and a firewall
5/4 matches – 4 marks
3 matches – 3 marks
2 matches – 2 marks
1 match – 1 mark
[4]
12 (a) code B
[1]
(b) Any one from:
– no need to understand workings of a computer
– easier to understand for programmer/closer to English
– much easier to debug
– much easier to test
– one-to-many when writing commands
– not machine-specific/portable
[1]
(c) Any one from:
– can address memory addresses directly
– no need for compilers/interpreters
– shorter code/code requires less storage/RAM
– can be written to run faster
[1]
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(d) –
–
–
–
–
compiler produces object code / interpreter doesn’t produce object code
compiler translates whole program in one go / interpreter translates and executes line at
a time
compiler produces list of all errors / interpreter produces error message each time an
error encountered
compiler produces “stand alone code” / interpreter doesn’t produce “stand alone code”
compilation process is slow but resultant code runs very quickly / interpreted code runs
slowly
[2]
13 (a) (i) 01000001
01000011
[2]
(ii) 41
43
[2]
(b) FA97
[4]
(c) –
–
[2]
© UCLES 2012
easier to identify values
easier to spot errors
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Cambridge International Examinations
Cambridge Ordinary Level
2210/02
COMPUTER SCIENCE
Paper 2 Problem-solving and Programming
For Examination from 2015
SPECIMEN PRE-RELEASE MATERIAL
No Additional Materials are required.
This material should be given to candidates up to six months before the examination.
READ THESE INSTRUCTIONS FIRST
Candidates should use this material in preparation for the examination. Candidates should attempt the
practical programming tasks using their chosen high-level, procedural programming language.
This document consists of 2 printed pages.
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2
Candidates’ preparation for the examination should include attempting the following practical
program coding tasks.
Write and test a program to complete the three tasks.
TASK 1
Input and store the names and marks for 30 students who have sat three computer science tests.
Test 1 is out of 20 marks, Test 2 is out of 25 marks, Test 3 is out of 35 marks. You must store the
names in a one-dimensional array and the marks and total score for each student in one-dimensional
arrays. All the marks must be validated on entry and any invalid marks rejected. You may assume
that the students’ names are unique.
TASK 2
Calculate and store the total score for each student and calculate the average score for the whole
class. Output each student’s name followed by their total score, then output the average score for the
class.
TASK 3
Select the student with the highest score and output their name and score.
Your program must include appropriate prompts for the entry of data. Error messages and other
output need to be set out clearly and understandably. All variables, constants and other identifiers
must have meaningful names. Each task must be fully tested.
Permission to reproduce items where third party owned material protected by copyright is included has been sought and cleared where possible. Every
reasonable effort has been made by the publisher (UCLES) to trace copyright holders, but if any items requiring clearance have unwittingly been included, the
publisher will be pleased to make amends at the earliest possible opportunity.
Cambridge International Examinations is part of the Cambridge Assessment Group. Cambridge Assessment is the brand name of University of Cambridge Local
Examinations Syndicate (UCLES), which is itself a department of the University of Cambridge.
© UCLES 2012
2210/02/SP/15
M.Mushtaq
03215275281
676
Cambridge International Examinations
Cambridge Ordinary Level
COMPUTER SCIENCE
2210/02
For Examination from 2015
Paper 2 Problem-solving and Programming
SPECIMEN PAPER
1 hour 45 minutes
Candidates answer on the Question Paper.
No Additional Materials are required.
READ THESE INSTRUCTIONS FIRST
Write your Centre number, candidate number and name in the spaces at the top of this page.
Write in dark blue or black pen.
You may use an HB pencil for any diagrams, graphs or rough working.
Do not use staples, paper clips, glue or correction fluid.
Calculators must not be used in this paper.
Answer all questions.
DO NOT ATTEMPT TASKS 1, 2 AND 3 in the pre-release material; these are for information only.
You are advised to spend no more than 40 minutes on Section A (Question 1).
No marks will be awarded for using brand names of software packages or hardware.
At the end of the examination, fasten all your work securely together.
The number of marks is given in brackets [ ] at the end of each question or part question.
This document consists of 13 printed pages and 3 blank pages.
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3
Section A
You are advised to spend no longer than 40 minutes answering this section.
Here is a copy of the pre-release material.
DO NOT attempt Tasks 1, 2 and 3 now.
Use the pre-release material and your experience from attempting the tasks before the examination to
answer Section A Question 1.
Pre-release material
Write and test a program to complete the three tasks.
TASK 1
Input and store the names and marks for 30 students who have sat three computer science tests.
Test 1 is out of 20 marks, Test 2 is out of 25 marks, Test 3 is out of 35 marks. You must store the
names in a one-dimensional array and the marks and total score for each student in one-dimensional
arrays. All the marks must be validated on entry and any invalid marks rejected. You may assume
that the students’ names are unique.
TASK 2
Calculate and store the total score for each student and calculate the average score for the whole
class. Output each student’s name followed by their total score, then output the average score for the
class.
TASK 3
Select the student with the highest score and output their name and score.
Your program must include appropriate prompts for the entry of data. Error messages and other
output need to be set out clearly and understandably. All variables, constants and other identifiers
must have meaningful names. Each task must be fully tested.
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1
(a) All variables, constants and other identifiers should have meaningful names.
(i) Declare the array to store the students’ names.
[1]
(ii) Declare the arrays to store each student’s marks and total score.
[2]
(b) (i) Show the design of your algorithm to complete Task 1 and Task 2 using pseudocode,
programming statements or a flowchart. Do not include any of the validation checks in
your algorithm.
[8]
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5
(ii) Comment on the efficiency of your design.
[1]
(c) Show two different sets of student data that you could use to check the validation used in
Task 1. Explain why you chose each data set.
Set 1
Reason for choice
Set 2
Reason for choice
[2]
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(d) (i) Explain how you select the student with the highest score (Task 3). You may include
pseudocode or programming statements to help illustrate your explanation.
[5]
(ii) How does your program work when there is more than one student having the highest
score? Explain using your method given in part (d)(i).
[1]
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7
Section B
2
Jatinder uses Internet banking.
This pseudocode checks her PIN.
c ← 0
INPUT PIN
x ← PIN
REPEAT
x ← x/10
c ← c + 1
UNTIL x < 1
IF c <> 5
THEN
PRINT “error in PIN entered”
ELSE
PRINT “PIN OK”
ENDIF
(a) What value of c and what message would be output if the following PINs were entered?
5 1 0 2 0 Value of c:
Message:
5120
Value of c:
Message:
[2]
(b) What type of validation check is being carried out here?
[1]
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8
3
The flowchart inputs the size of a number of car engines; a value of –1 stops the input.
This information is output: average engine size and number of engines with size > 1.5
START
Engine ← 0
Count ← 0
Number ← 0
INPUT Size
is Size
= 1 ?
Yes
Average ← Engine/Number
OUTPUT
Average, Count
No
is Size
> 1.5 ?
Yes
STOP
Count ← Count + 1
No
Number ← Number + 1
Engine ← Engine + Size
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Complete the trace table for the input data.
1.8, 2.0, 1.0, 1.3, 1.0, 2.5, 2.0, 1.3, 1.8, 1.3,
Engine
Count
Number
Size
–1
Average
OUTPUT
[6]
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10
4
Read this section of program code that inputs twenty (20) numbers and then outputs the largest
number input.
1
h = 0
2
c = 0
3
REPEAT
4
READ x
5
IF x > h THEN x = h
6
c = c + 1
7
PRINT h
8
UNTIL c < 20
There are three errors in this code.
Locate these errors and suggest a corrected piece of code.
1
2
3
[3]
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5
A floor turtle uses these instructions.
Instruction
Meaning
FORWARD d
Move d cm forward
BACKWARD d
Move d cm backward
LEFT t
Turn left t degrees
RIGHT t
Turn right t degrees
REPEAT n
Repeat the next set of instructions n times
ENDREPEAT
End of REPEAT loop
PENUP
Raise the pen
PENDOWN
Lower the pen
(Each square in the drawing is 10 cm by 10 cm.)
Start
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Finish
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Complete the set of instructions to draw the shape (shown in bold lines).
PENDOWN
LEFT 90
REPEAT
[5]
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6
(a) Write an algorithm, using pseudocode or flowchart only, which:
•
•
inputs three numbers
outputs the largest of the three numbers
[3]
(b) Write an algorithm, using pseudocode or flowchart only, which:
•
•
inputs 1000 numbers
outputs how many of these numbers were whole numbers (integers)
(You may use INT(x) in your answer, e.g. y = INT(3.8) gives the value y = 3)
[4]
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(c) Describe, with examples, two sets of test data you would use to test your algorithm.
1
2
[2]
7
A database was set up to show the properties of certain chemical elements. Part of the database
is shown below.
Name of
element
Element
symbol
Atomic
number
Atomic
weight
Melting
point (C)
Boiling
point (C)
State at
room temp
oxygen
O
8
16
–218
–183
gas
iron
Fe
26
56
1538
2861
solid
mercury
Hg
80
201
–38
356
liquid
bromine
Br
35
80
–7
59
liquid
osmium
Os
76
190
3033
5012
solid
caesium
Cs
55
133
28
671
solid
gallium
Ga
31
70
30
2204
solid
argon
Ar
18
40
–189
–186
gas
silver
Ag
47
108
961
2162
solid
(a) How many fields are in each record?
[1]
(b) The following search condition was entered:
(Melting point (C) < 40) AND (Atomic weight > 100)
Using Element symbol only, which records would be output?
[2]
(c) Which field would be best suited as primary key?
[1]
© UCLES 2012
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Cambridge International Examinations
Cambridge Ordinary Level
COMPUTER STUDIES
2210/02
For Examination from 2015
Paper 2 Problem-solving and Programming
SPECIMEN MARK SCHEME
1 hour 45 minutes
MAXIMUM MARK: 50
This document consists of 6 printed pages.
[Turn over
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2
Section A
1
(a) (i) Many correct answers, they must be meaningful. This is an example only.
StudentNames[1:30]
[1]
(ii) Many correct answers, they must be meaningful. This is an example only.
StudentMarksTest1[1:30]
StudentMarksTest2[1:30]
StudentMarksTest3[1:30] (1 mark)
StudentTotalScore[1:30] (1 mark)
[2]
(b) (i) –
–
–
–
–
–
–
–
outside loop zeroing total for loop (sum in example below)
loop for all students
input name and all test scores
in loop adding a student’s total
storing the total
inside loop printing student’s name and total
outside loop calculating class average
printing class average
sample algorithm:
Sum 0
FOR Count 1 TO 30
INPUT Name
StudentName[Count] Name
INPUT Mark1, Mark2, Mark3
StudentMarksTest1[Count] Mark1
StudentMarksTest2[Count] Mark2
StudentMarksTest3[Count] Mark3
Total Mark1 + Mark2 + Mark3
StudentTotalScore[Count] Total
Sum Sum + Total
PRINT StudentName[Count], StudentTotalScore[Count]
NEXT Count
ClassAverage = Sum/30
PRINT ClassAverage
(ii) any relevant comment with regards to efficient code (e.g. single loop)
(c)
[8]
[1]
Many correct answers, these are examples only.
1 mark per data set and reason
Set 1:
20, 25, 30, 35
Reason: valid data to check that data on the upper bound of each range check is
accepted
Set 2:
21, 26, 31, 36
Reason: invalid data to check that data above the upper bound of each range check is
rejected
[2]
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(d) (i) Maximum 5 marks in total for question part
Maximum 3 marks for algorithm
Description (max 3)
– set variable called HighestScore to zero and variable called BestName to dummy
value
– loop 30 times to check each student’s total score in turn
– check student’s score against HighestScore
– if student’s score > HighestScore then
– … replace value in HighestScore by student’s score and store student’s name in
BestName
– output BestName and HighestScore outside the loop
Sample algorithm (max 3):
HighestScore 0
BestName “xxxx”
FOR Count 1 TO 30
IF StudentTotalScore[Count] > HighestScore
THEN
HighestScore StudentTotalScore[Count]
BestName StudentName[Count]
ENDIF
NEXT Count
PRINT BestName, HighestScore
(1 mark)
(1 mark)
(1 mark)
(1 mark)
(1 mark)
If algorithm or program code only, then maximum 3 marks
[5]
(ii) comment on which student(s)’ name will be output
e.g. The first student with the highest score will be output
© UCLES 2012
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Section B
2
(a) 1 mark for value of c and message
51020: value of c:
message:
5
PIN OK
(1 mark)
5120:
4
error in PIN entered
(1 mark)
value of c:
message:
[2]
(b) length check
[1]
3
Engine
Count
Number
Size
0
0
0
1.8
1.8
1
1
2.0
3.8
2
2
1.0
4.8
3
1.3
6.1
4
1.0
7.1
5
2.5
9.6
3
6
2.0
11.6
4
7
1.3
8
1.8
9
1.3
10
–1
12.9
14.7
5
16.0
Average
OUTPUT
1.6
(1 mark)
4
(1 mark)
(1 mark)
(1 mark)
(1 mark)
1.6, 5
(1 mark)
[6]
1 mark for each error identified + suggested correction
line 5:
this should read IF x > h THEN h = x
line 7:
PRINT h should come after the end of the repeat loop
line 8:
this should read UNTIL c = 20 or UNTIL c >= 20 or UNTIL c > 19
© UCLES 2012
[3]
2210/02/SM/15
M.Mushtaq
03215275281
693
5
5
PENDOWN
LEFT 90
REPEAT 3
FORWARD 30
RIGHT 90
------------------------------------------------------------------------------------------ENDREPEAT
FORWARD 10
LEFT 90
OR
PENUP
------------------------------------------------------------------------------------------PENUP
OR
LEFT 90
FORWARD 10
PENDOWN
------------------------------------------------------------------------------------------REPEAT 2
OR
REPEAT 3
FORWARD 20
------------------------------------------------------------------------------------------RIGHT 90
ENDREPEAT
FORWARD 20
OR
(LEFT/RIGHT 180)
(LEFT 90)
(1 mark)
(1 mark)
(1 mark)
(1 mark)
(1 mark)
Alternative answer for last 2 marks:
FORWARD 20
RIGHT 90
------------------------------------------------------------------------------------------FORWARD 20
RIGHT 90
FORWARD 20
(1 mark)
(1 mark)
Give a mark for each correct group of statements
© UCLES 2012
2210/02/SM/15
M.Mushtaq
[5]
[Turn over
03215275281
694
6
6
(a) marking points:
the way to find and print the largest value a
the way to find and print the largest value b
the way to find and print the largest value c
sample algorithm:
INPUT a, b, c
IF a > b AND a > c THEN PRINT a
ELSE IF b > c THEN PRINT b
ELSE PRINT c
(b) marking points:
loop construct
check if number is an integer
counting the number of integers input
output count value (outside the loop)
sample algorithm:
FOR x ← 1 TO 1000
INPUT Number
Difference ← INT(number) – Number
IF Difference = 0 THEN Total ← Total + 1
NEXT x
PRINT total
(NOTE: alternative to lines 3 and 4:
IF INT(Number) = Number THEN Total ← Total + 1
1 mark
1 mark
1 mark
(1 mark)
(1 mark)
(1 mark)
[3]
1 mark
1 mark
1 mark
1 mark
(1 mark)
(1 mark)
(1 mark)
(1 mark)
(2 marks) )
[4]
(c) Description of any two sets of test data. Many correct answers, these are examples only.
1000 whole numbers to ensure that loop works properly
900 whole numbers and 100 numbers with decimal places to ensure that the routine
distinguishes correctly
[2]
7
(a) 7
[1]
(b) Hg, Cs
[2]
(c) Element symbol
[1]
© UCLES 2012
2210/02/SM/15
M.Mushtaq
03215275281