A 20-mile road runs between Buzzardtown and Dry Gulch. Each town has a gas station,
but there are no gas stations between the towns. Let x be the distance in miles from
Buzzardtown, measured along the road (so 0 ≤ x ≤ 20), and y be the distance in miles to
the nearest gas station. Make a table of values that includes entries for x = 7, x = 9, and
x = 16, and then draw a graph of y versus x. The graph should have a vertex at (10, 10).