A rock is thrown into a lake from a bridge 133 feet above the lake's surface. The rock sinks 78 feet below the lake's surface. What is the difference between the elevations?

Responses
A 55 feet55 feet
B 211 feet211 feet
C −55 feet−55 feet
D −211 feet

The difference between the elevations is the distance from the bridge to the lake's surface minus the distance the rock sinks below the lake's surface.

The distance from the bridge to the lake's surface is 133 feet.
The distance the rock sinks below the lake's surface is 78 feet.

Therefore, the difference between the elevations is 133 - 78 = 55 feet.

Answer: A) 55 feet