A Spectator Watches a Rowing Race from the Edge of a River

question 286

Multiple Choice

A spectator watches a rowing race from the edge of a river bank. The lead boat is moving in a straight line that is 90 ft from the river bank. If the boat is moving at a constant speed of 20 ft/sec, how fast is the boat moving away from the spectator when it is 400 ft past her?

• A) 26.94 ft/sec
• B) 17.28 ft/sec
• C) 61.85 ft/sec
• D) 19.51 ft/sec

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Definitions:

Topographic Map

A map that represents the three-dimensional surface of the earth using contour lines to show elevation changes.

Geologic Map

A map that shows the distribution, nature, and age relationships of rock units, sediments, structures, and other geologic features.

Topographic Relief

The difference in elevation of one feature relative to another; synonym: relief.

Stratigraphic Section

A vertical profile or cross-section through sedimentary rocks or soils showing the sequence and relationship of strata.