LAB MODULE 2: THE GEOGRAPHERS’ TOOLS
Note: Please refer to the GETTING STARTED lab module to learn tips on how to set up and
maneuver through the Google Earth ( ) component of this lab.
KEY TERMS
The following is a list of important words and concepts used in this lab module:
Absolute location
Aerial photographs
Geographic Information
System (GIS)
Land Use/Land Cover
Remote sensing
Cartographer
Contours, contour lines
Larger scale map
Latitude
Satellite images
(Landsat)
Scale
Slope
Contour interval (CI)
Longitude
Small scale map
Coordinate systems
Map scale (Scale)
Spatial analysis
False color composite
Map types
Thematic maps
Geospatial technologies
Relative location
LAB MODULE LEARNING OBJECTIVES
After successfully completing this lab module, you should be able to:






Use latitude and longitude to find an absolute location
Explain the difference between large and small scale maps
Calculate map scale
Identify and describe the three types of maps
Interpret contour maps
Identify changes in land use and land cover using remotely sensed images
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INTRODUCTION
This lab module examines fundamental concepts and tools geographers use to study the Earth.
Topics include latitude and longitude, absolute and relative location, geospatial technologies,
map types and scale. While these topics may seem disparate, you will learn how they are
inherently related.
The modules start with four opening topics, or vignettes, found in the accompanying Google
Earth file. These vignettes introduce basic concepts related to geospatial tools and
technologies. Some of the vignettes have animations, videos, or short articles that will provide
another perspective or visual explanation for the topic at hand. After reading each vignette and
associated links, answer the following questions. Please note that some components of this lab
may take a while to download or open, especially if you have a slow internet connection.
Expand GEOGRAPHER’S TOOLS, and then expand the INTRODUCTION folder. Double click
Topic 1: Tools for Geography.
Read Topic 1: Tools for Geography.
Question 1: According to the article, what are three geographic technologies
geographers use to study the Earth?
A.
B.
C.
D.
GIS, GPS, and compasses
GPS, remote sensing, and GIS
GIS, AutoCAD, and remote sensing
GPS, Glovis, and GIS
Read Topic 2: Maps.
Question 2: In what state was the first topographic map (relief map using contour lines)
issued in the United States?
A.
B.
C.
D.
Delaware
Louisiana
Maryland
Mississippi
Read Topic 3: Coordinate Systems and Location.
Question 3: What continent is found at grid cell 35N?
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A.
B.
C.
D.
The continent of Africa
The continent of Australia
The continent of Europe
The continent of South America
Read Topic 4: Geospatial Technologies.
Question 4: Looking at the map layers on the vignette image, which layers would be
most likely remotely sensed data?
A.
B.
C.
D.
States and cities
Countries and Territories
Background
Radar and Satellite
Collapse and uncheck INTRODUCTION.
GLOBAL PERSPECTIVE
Latitude and Longitude form a grid on the Earth’s surface, enabling us to determine an absolute
location for any given place or phenomenon.
Expand GLOBAL PERSPECTIVE.
Turn on the latitude and longitude grid by selecting View > Grid, or by using the keyboard
shortcut CTRL + L ( + L on the Mac)
Lines of latitude, or parallels, divide the globe at the Equator, and run parallel in both the
Northern and Southern Hemispheres (Figure 1). Locations in the Northern Hemisphere are
denoted with an N (or a positive number), while locations in the Southern Hemisphere are
denoted with an S (or a negative number). The parallel at the Equator is 0°N or 0°S, and
increases to 90°N (or +90) at the North Pole, and 90°S (or -90) at the South Pole.
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Latitude (parallels)
Longitude (meridians)
Figure 1. Lines of latitude (parallels) and longitude (meridians) (Arbogast)
Double-click and select Prime Meridian.
Lines of longitude, or meridians, run from pole to pole. Along the Prime Meridian (which runs
through Greenwich, UK), the Earth is divided into Eastern and Western Hemispheres. Locations
in the Eastern Hemisphere are denoted with an E (or a positive number), while locations in the
Western Hemisphere are denoted with a W (or a negative number). The Prime Meridian is 0°E
or 0°W, and increases to toward 180°E (or +180) or 180°W (or -180).
Latitude and longitude are measured in degrees, minutes, and seconds. Similar to a clock,
where one hour equals 60 minutes, and one minute equals 60 seconds, each degree of latitude
or longitude can be divided into 60 minutes (60’) and each minute of latitude or longitude can
be further subdivided into 60 seconds (60”). For example, the White House in Washington, DC
is located at 38° 53’ 51” N, 77° 02’ 11” W. Latitude and longitude can also be measured in
decimal degrees, or degrees and decimal minutes, by converting the minutes and/or seconds
into decimal fractions. Cardinal directions (North, East, South and West) are replaced with
positive or negative signs. Therefore, the absolute location of the White House in decimal
degrees would be 38.8976, -77.0365.
Click Exit Street View in the top right corner of the Google Earth 3D viewer.
Change your units to degrees, minute and seconds. (Refer to the GETTING STARTED lab
module for directions on how to change latitude and longitude units).
Double-click and select Location A.
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Question 5: What are the latitude and longitude coordinates for Location A?
A.
B.
C.
D.
51N, 114E
114S, 51 E
51S, 114W
51N, 114W
Double-click and select Location B.
Question 6: What are the latitude and longitude coordinates for Location B?
A.
B.
C.
D.
53N 6E
6N, 53E
53S, 6W
53N, 6W
Question 7: Which is closer – the distance between Location A and the Equator or the
distance between Location B and the Equator?
A.
B.
C.
D.
Location A and the Equator
Location B and the Equator
Locations A and B are the same distance from the Equator
Cannot discern from the information provided
Question 8: Which is closer – the distance between Location A and the Prime Meridian
or the distance between Location B and the Prime Meridian?
A.
B.
C.
D.
Location A and the Prime Meridian
Location B and the Prime Meridian
Locations A and B are the same distance from the Prime Meridian
Cannot discern from the information provided
Double-click and select Location C.
Question 9: What are the latitude and longitude coordinates for Location C?
A.
B.
C.
D.
50N, 68S
50N, 68W
50S, 68E
50S, 68W
Question 10: Which is farther– the distance between Location B and the Equator or the
distance between Location C and the Equator?
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A.
B.
C.
D.
Location B and the Equator
Location C and the Equator
Locations B and C are the same distance from the Equator
Cannot discern from the information provided
Question 11: Which is farther – the distance between Location A and the Prime
Meridian or the distance between Location C and the Prime Meridian?
A.
B.
C.
D.
Location A and the Prime Meridian
Location C and the Prime Meridian
Locations A and C are the same distance from the Prime Meridian
Cannot discern from the information provided
Collapse and uncheck GLOBAL PERSPECTIVE.
Turn off the latitude/longitude grid (CTRL + L, or
+ L on the Mac).
MAP SCALES
Map scale (or scale) is the ratio of the distance between two features or absolute locations on
the map and the distance between the same two features or absolute locations on the ground.
Maps should provide a scale to the user; typically, map scales are shown in the bottom margin
of the map.
Map scales are expressed in four ways: ratio, representative fraction, verbal scale (also called a
lexical scale), and bar scale (also called a scale bar, graphic scale or graphical scale). An example
of each of these map scales is illustrated below.
Scale Expression
Ratio
1:12,000
Representative Fraction (RF)
1/12,000
Verbal
1 inch equals 1,000 feet
Scale Bar
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Expand MAP SCALES and then double-click and select Boothbay Harbor (Note: The
topographic map might take a few seconds to display). To close the citation, click the X in the
top right corner of the window.
Question 12: How is the scale on this map expressed or presented (Hint: look toward
the bottom of the map image)?
A.
B.
C.
D.
Scale bar and RF
RF and Verbal
Verbal and Ratio
Scale Bar and Ratio
If you enlarge (zoom in) or reduce (zoom out) of the map, the scale of the image changes, but
the scales found the map do not. It is important to note only a bar scale can be used to make
distance calculations to a map that is enlarged or reduced because it is the only map scale that
remains correct if the map size changes.
If a bar scale is not provided, it is important to know how to calculate distance. In Google Earth,
the Ruler tool will help you calculate the approximate distance between two (or more) points.
To calculate scale, we will use the equation
S=
𝒅
𝑫
where:

S = scale

d = distance between two features on the map

D = distance between two feature on the ground
Whether using the metric system or the British/Imperial system, make sure that you know the
conversions between the units.
Metric Units
British/Imperial Units
1m
=
100 cm
1 ft
= 12 in
1 km
=
1000 m
1 mile
= 5,280 ft
1 km
=
100,000 cm
1 mile
= 63,360 in
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𝒅
Now for an example that will use the scale equation (S = ) and British/Imperial units.
𝑫
Example 1: Two buildings are 8 inches apart on a map (d). The same buildings are 16,000
feet apart on the ground (D). Calculate the scale of the map.
To calculate the scale, first let’s make sure that are units are the same. Currently, the map units
(d) are in inches and the ground units (D) are in feet. Therefore, we will convert feet to inches.
We know there are 12 inches in a foot, so we can multiply D by 12 to convert the distance on
the ground from feet (ft) to inches (in).
D = 16,000 ft.
D = 16,000 ft. x 12 inches/ft. = 192,000 inches
Now we can use the equation
S=
S=
𝒅
𝑫
𝟖 𝒊𝒏
𝟏𝟗𝟐,𝟎𝟎𝟎 𝒊𝒏
Because we are dividing the same unit in the numerator as the denominator, the units (inches)
cancel out.
S=
𝟖
𝟏𝟗𝟐,𝟎𝟎𝟎
Now we need to simplify the equation so that our numerator is a 1. We can do this by dividing
both the numerator and the denominator by 8.
S=
S=
𝟖/𝟖
𝟏𝟗𝟐,𝟎𝟎𝟎/𝟖
𝟏
𝟐𝟒,𝟎𝟎𝟎
This ratio can also be written as 1:24,000.
Example 2: Calculate the scale of a map in which the distance between two features is 6” on
the map (d) and 12 miles on the ground (D).
Again, to calculate the scale, we first need to convert distances into the same units. There are
63,360 inches in a mile. If we multiply 12 miles by 63,360 we can convert D into inches
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D = 12 miles
D = 12 miles x 63,360 inches/mile = 720,360 inches
Now we can use the equation
S=
S=
𝒅
𝑫
𝟔 𝒊𝒏
𝟕𝟐𝟎,𝟑𝟔𝟎 𝒊𝒏
=
𝟔
𝟕𝟐𝟎,𝟑𝟔𝟎
Because we are dividing the same unit in the numerator as the denominator, the units (inches)
cancel out.
Now we need to simplify the equation so that our numerator is a 1. We can do this by dividing
both the numerator and the denominator by 6.
S=
𝟔/𝟔
𝟕𝟐𝟎,𝟑𝟔𝟎/𝟔
=
𝟏
𝟏𝟐𝟔,𝟕𝟐𝟎
This ratio can also be written as 1:126,720
Notice that Examples 1 and 2 have different map scales. The map scale in Example 1, at
1:24,000, is larger than the map scale in Example 2, at 1:126,760.
Large-scale maps are more zoomed in and therefore show more detail, but less area.
Conversely, small scale maps are more zoomed out and therefore show less detail but more
area. Figures 2 and 3 illustrate larger and smaller map scales.
Figure 2. Map with a 1:24,000 scale (larger scale map) (USGS)
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Figure 3. Map with 1:62,500 scale (smaller scale map) (USGS)
Example 3. What is the distance on a map (d) in centimeters between two features if they
are 5km apart on the ground (D) and the map has a scale (S) of 1:100,000?
First, we need to rearrange our equation so that we are solving for map distance rather than
scale.
S=
𝒅
𝑫
rearranged to d = S * D
Because Scale (S) is unitless, we do not have to worry yet about converting units. To note, the
Scale ratio of 1:100,000 can be rewritten as 1/100,000.
d=S*D
d=
𝟏
* 5km =
𝟏𝟎𝟎,𝟎𝟎𝟎
𝟓𝒌𝒎
𝟏𝟎𝟎,𝟎𝟎𝟎
d = 0.00005km
Because we are solving for map distance (d), it is unlikely that the final answer will be in
kilometers, and far more likely to be in centimeters. So, we convert km to cm.
d = 0.00005km *
𝟏𝟎𝟎,𝟎𝟎𝟎 𝒄𝒎
𝟏𝒌𝒎
d = 5cm
Example 4. What is the distance on the ground in kilometers between two features if they
are 5cm apart on the map and the map has a scale of 1:50,000?
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First, we need to rearrange our equation so that we are solving for map distance rather than
scale.
S=
𝒅
rearranged to D =
𝑫
𝒅
𝑺
Next, we solve the equation.
D=
𝒅
𝑺
=
𝟓𝒄𝒎
𝟏⁄𝟓𝟎,𝟎𝟎𝟎
=
𝟓𝒄𝒎∗𝟓𝟎,𝟎𝟎𝟎
𝟏
= 250,000cm
Because we are solving for ground distance (D), it is unlikely that the final answer will be in
centimeters, and far more likely to be in kilometers. So, we convert cm to km.
D=
𝟐𝟓𝟎,𝟎𝟎𝟎𝒄𝒎
𝟏𝟎𝟎,𝟎𝟎𝟎𝒄𝒎⁄𝟏𝒌𝒎
= 2.5km
Question 13. Using Figure 4, calculate the distance on the ground, in miles, between
Mill Point and Oak Point. Assume we measured 5 inches as the map distance, and know
that the map scale is 1:63,360.
Figure 4. Mill and Oak Points (USGS)
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A.
B.
C.
D.
5 inches * 63,360 inches = 316,800 inches = 60 miles
5 inches * 63,360 inches = 316,800 inches = 5 miles
5 inches / 63,360 inches = .0000799 miles = 41.7 feet
63,360 inches / 5 inches = 12,672 inches = 2.4 miles
Question 14: What is the distance on a map in centimeters between two features if they
are 7.6 km apart on the ground and the map has a scale of 1:125,000?
A.
B.
C.
D.
7.6 km * (1/125,000) = 0.0000608 cm
7.6 km * (1/125,000) = 6.08 cm
7.6 km / (1/125,000) = 95 cm
7.6 km / (1/125,000) = 950,000 cm
Google Earth does not provide scale as a ratio, representative fraction, or a verbal scale. It does,
however, provide a bar scale, found in the lower left hand corner of the screen. If it is not
active, select View > Scale Legend.
Even if it seem counterintuitive, remember! the larger the distance on the bar scale, the smaller
the map scale. Likewise, the smaller the distance on the bar scale, the larger the map scale.
Double-click and select Squirrel Island 1.
Question 15: What is the approximate distance, in feet, represented by the scale bar?
A.
B.
C.
D.
~
~
~
~
4000 ft
5800 ft
6600 ft
7400 ft
Uncheck Squirrel Island 1. Double-click and select Squirrel Island 2.
Question 16:What is the approximate distance, in feet, represented by the scale bar?
A.
B.
C.
D.
~ 1150 ft
~ 1350 ft
~ 1550 ft
~ 1950 ft
Question 17: Which bar scale represents the smaller map scale – Squirrel Island 1 or
Squirrel Island 2?
A. Squirrel Island 1
B. Squirrel Island 2
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C. They are the same
D. Unable to determine from information provided
Collapse and uncheck MAP SCALES.
CONTOURS
Contours are lines that connect places of equal elevation. A contour interval (CI) is the elevation
difference between two consecutive contour lines, and is commonly provided in the margin of a
map. In Figure 5, the CI is 10 feet, meaning each consecutive contour line represents a 10 foot
change in elevation.
Index contours are typically labeled and are have a heavier line weight than regular contour
lines. In Figure 5, the index contours are found every 50 feet (every 5 contour lines). The Index
contours at 50, 100, and 150 feet are labeled on the contour map.
There some rules regarding
contour lines:


Contour lines always
form a closed polygon
(see A in Figure 5).
However, on some maps,
contour lines might run
off the margin.
Contour lines spaced
closer together depict a
steeper slope (see B in
Figure 5). In contrast,
contour lines spaced
farther apart (wider
spacing) depicts a gentler
slope or flat area.
A
C
z
D
B

Contour lines might
Figure 5. Contours (USGS)
touch where there is a
steep elevation change, like a steep slope or cliff. Contour lines never cross unless the cliff
face has an overhanging ledge (hidden contours are then depicted as dashed lines).

Concentric, closed contours denote a hill or summit (see C in Figure 5); whereas closed
contours with hachure marks on the downslope side depicts a depression.
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
Wherever contour lines cross a river point, the lines point upstream and create a V-shaped
pattern (see D in Figure 5).
Double-click and expand CONTOURS.
Double-click and select Boothbay Harbor. (Note: The topographic map might take a few
seconds to display). To close the citation, click the X in the top right corner of the window.
A USGS 7.5” map will appear near Georgetown, Maine. You might have to pan and zoom in or
out to answer the following questions.
Question 18: What is the contour interval of this map?
A.
B.
C.
D.
10 meters
24,000 feet
10 feet
24,000 meters
Double-click and select MacMahan Island.
Question 19: What is the index contour interval shown on MacMahan Island?
E.
F.
G.
H.
Every 20 feet
Every 40 meters
Every 50 feet
Every 100 meters
Unselect MacMahan Island. Double-click and select Red Squares.
Question 20: What is the highest elevation within the two squares?
A.
B.
C.
D.
150 meters
150 feet
175 feet
93 feet
Question 21: Within the right red square, determine the general downstream direction
of the river.
A. North
B. East
C. South
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D. West
Question 22: Explain what contour rule helped you answer Question 22.
A.
B.
C.
D.
Contours are spaced close together
Contours form closed polygons
Contours form a V shape that points upstream
Contours form a V shape that points downstream
Question 23: Within these two red squares, where is the steepest slope located?
A.
B.
C.
D.
Left edge of right square
Left edge of left square
Middle of right square
Middle of left square
Question 24: Within these two red squares, where is the flattest area?
A.
B.
C.
D.
Left edge of left square
Upper right corner of right square
Upper center of left square
Upper center of right square
Uncheck Red Squares.
Double-click and select Slope 1. Next, change the elevation exaggeration to 2 (see GETTING
STARTED lab module on how to change exaggeration). Double-click and select Perspective
view to see the landscape in three dimensions.
Question 25: As you move from left to right across the yellow line, is the elevation
increasing or decreasing?
A.
B.
C.
D.
Increasing
Decreasing
Remaining flat
Unable to determine from information provided
Right-click on Slope 1 and select Show Elevation Profile.
At the bottom of the screen is a cross section of the terrain for the yellow line. The X axis of the
elevation profile chart is the distance of the line, while Y axis of the charge represents the
elevation over the line distance. As you run the cursor along the line, the corresponding
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location along the profile is identified. Additional information regarding elevation, distance, and
slope is found immediately above the elevation profile.
Question 26: What is the approximate length of the profile line (distance), in feet?
A.
B.
C.
D.
~ 131 feet
~ 161 feet
~ 966 feet
~ 5280 feet
Question 27: What is the change in elevation (the relief) from one end of the line to the
other, in feet?
A.
B.
C.
D.
~ 131 feet
~161 feet
~ 966 feet
~ 5280 feet
Question 28: Slope is the rise (relief of the line) divided by the run (distance of the line).
Using your answers from the previous two questions, calculate the percent slope of the
line to the nearest integer.
𝑹𝒊𝒔𝒆
𝑹𝒖𝒏
A.
B.
C.
D.
*100 = (________ /_______) *100 = ______________
(131 feet / 161 feet) * 100 = 81%
(161 feet / 966 feet) * 100 = 17%
(966 feet / 5280 feet) * 100 = 18%
(966 feet / 161 feet) * 100 = 600%
Collapse and uncheck CONTOURS.
REMOTE SENSING
Remote sensing is the art and science of acquiring information about a feature or phenomenon
without being in direct contact of that feature or phenomenon. In this part of the lab, you will
explore land use and land cover change using satellite imagery. For the rest of this lab, you will
be working with Landsat satellite imagery, which is considered the longest continuous global
record of Earth’s surface.
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Expand REMOTE SENSING and click NASA Landsat Flyby.
Note: Some Mac users might have to click the following URL to view the Flyby video:
https://www.youtube.com/watch?v=ZZx1xmNGcXI
Question 29: How long has Landsat been collecting data on Earth?
A.
B.
C.
D.
Since 1968
Since 1953
Since 1977
Since 1972
Question 30: Natural disasters like the Mount St. Helens eruption and urban growth in
places like Las Vegas are two uses of Landsat data. Based on the video, name two
additional physical geography topics – and their example locations – for which Landsat
imagery has been used.
A.
B.
C.
D.
Mosquito habitat, Mississippi & Oil exploration, Canada
Climate change, Antarctic & Flooding, North Carolina
Ecosystems, North Carolina & Mosquito habitat, Yemen
Oil exploration, Yemen & Farmland, Kansas
Uncheck NASA Landsat Flyby.
Click Landsat Viewer. (Note: if the webpage does not open or takes too long to load, open
the web browser outside of Google Earth by choosing the browser icon at the top left corner
of the Google Earth Viewer.)
In the ESRI web site, go to the top right hand corner and select View larger. The default image
should be Mount St. Helens, in Washington, USA. If it is not, type Mount St. Helens in the
search field and then press Enter. To zoom in or out, use any slider found in the top left-hand
corner of an image area. Assume North is at the top of these remotely sensed images.
The images in the left (1975) and center (2000) panels are called false color composite images.
The satellite sensors collect data from the non-visible portion of the electromagnetic spectrum
(that is to say, wavelengths outside of the visible portion of the electromagnetic spectrum we
see with our eyes). Specifically, the images are displaying reflected infrared energy; these are
wavelengths longer than visible light. Vegetation reflects a great amount of this energy, and
appears red in these images. The image to the far right shows change or difference between
the 1975 and 2000 images. For a further interpretation of colors, see the legends found below
the images.
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Question 31: What direction was most impacted by the 1980 Mount St. Helen’s
eruption?
A.
B.
C.
D.
North
East
South
West
Question 32: How did you determine this from the remote sensing imagery?
A.
B.
C.
D.
The significant decrease in vegetation
The Swift Reservoir is smaller in the 2000 image
Spirit Lake in 1975 is now 2 separate lakes in 2000
Forests have grown back.
Type Las Vegas, Nevada in the search field and then press Enter. You can pan or zoom in or
out of the image to answer the following questions.
Question 33: What does the “white” in the change detection image (right panel)
represent?
A.
B.
C.
D.
Increased vegetation
Decreased vegetation
No change
Clouds
Question 34: In which direction has the majority of urban growth occurred between
1975 and 2000?
E.
F.
G.
H.
North
East
South
All directions
Question 35: What are the bright red (green in the change detection image) rectangle
features that are predominately found on the west side of Las Vegas?
A.
B.
C.
D.
New casinos
New subdivisions
New golf courses
New water parks
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Question 36: Is urbanization in this region linked to an overall increase, decrease, or no
change in vegetation land cover?
A.
B.
C.
D.
Increase
Decrease
Roughly the same
Unable to tell from information provided
Question 37: Present in both 1975 and 2000, what is the diagonal strip running NE to
SW through the middle of the city?
A.
B.
C.
D.
Dried river bed
Airport runway
The famous Las Vegas “Strip”
A major interstate highway
Collapse and uncheck REMOTE SENSING. You have completed Lab Module 2.
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