Step 7. Formal Assessment
1.
The following code initializes the variables x and y:
int x = 3; int y = 5;
What is the data type of the value of the expression (x / y)?
a.
b.
c.
d.
e.
2.
number
int
double
cast
operator
The following code initializes the variables x and y:
int x = 3; double y = 1.0;
What is the data type of the value of the expression (x % y)?
a.
b.
c.
d.
e.
3.
number
int
double
cast
operator
After this code is executed, what is the value of z?
double x = 2.5;
double y = (2 * x);
double z;
z = (int)(x + (2 * y));
The value of z is
a.
b.
c.
d.
e.
5.0
12
12.0
12.5
None of the above — an error occurs.
Which is greater:
a. 3 – 42 or (3 – 4)2
b. 3 x 7 + 9 or 3 x (7 + 9)
c. 12 + 8/2 or (12 + 8)/2
d. 4 – 16/42 or 4 – (16/4)2
4.
5.
the answer is (3 - 4)2 = 1
the answer is 3 x (7 + 9)
the answer is 12 + 8/2
the answer is 4 – 16/42
After this code is executed, what is the value of z?
int x = 2.5;
int y = (2 * x);
int z = y / 2;
The value of z is
a.
b.
c.
d.
e.
6.
2
2.5
3
5
None of the above — an error occurs.
What is the value of ((int)-5.2 + 1)?
a.
b.
c.
d.
-4
-5
-7
NaN
e. None of the above — an error occurs.
7.
What is the remainder of 376 / 30?
The answer is 16
8.
Which of these expressions evaluates to 1.0?
a.
b.
c.
d.
e.
3/2
(double)3 / (double)2
(double)(3 / 2)
3 / (double)2
(double)3 / 2
9.
After this code is executed, what is the value of p?
int r = 5;
r++;
int p = r;
r--;
The value of p is
a.
b.
c.
d.
e.
4
5
6
7
None of the above
Suppose that the variables a, b and c are initialized as follows:
10.
int a = 10;
int b = 14;
int c = 25;
Which of these expressions evaluates to the arithmetic mean of a, b and c?
a.
b.
c.
d.
e.
11.
(double)a + (double)b + (double)c / 3.0
(a + b + c) / 3
(a + b + c) / 3.0
(double)((a + b + c) / 3)
None of the above.
After this code is executed, what is the value of x?
double x = 4.5;
double y = 5.4;
int z = 5;
x += (int)x + (int)y / z;
The value of x is
a.
b.
c.
d.
e.
5
5.5
9
9.5
None of the above.
12.
A traffic light cycles through three different colors; green to yellow to red. If the light is
green now, what color will it be after 976 changes?
Yellow. When you divide 976 by 3 the remainder is 1. Therefore the light is one color past
green.
13.
Make a program that prompts the user the current temperature in Fahrenheit
degree and convert to Celsius. Then write a second program for Celsius and
convert into Fahrenheit. The formula from Fahrenheit to Celsius is Tc = (5/9)*(Tf-32)
and from Celsius to Fahrenheit is Tf = (9/5)*Tc+32.
// simple program that converts from Fahrenheit to Celsius
import java.util.Scanner;
public class FromFtoC {
public static void main(String[] args) {
double degreesF, degreesC;
Scanner console = new Scanner(System.in);
System.out.println("What's current Fahrenheit temperature? ");
degreesF = console.nextDouble();
degreesC = 5.0/9.0 * (degreesF - 32);
System.out.print("That corresponds to " + degreesC + "in
Celsius");
}
}
// simple program that converts from Fahrenheit to Celsius
import java.util.Scanner;
public class FromCtoF {
public static void main(String[] args) {
double degreesF, degreesC;
Scanner console = new Scanner(System.in);
System.out.println("What's current Celsius temperature? ");
degreesC = console.nextDouble();
degreesF = (9.0/5.0) * degreesC + 32;
System.out.print("That corresponds to " + degreesF + " in
Fahrenheit");
}
}