Question

Lisa is standing on a dock beside a lake. She drops a rock from her hand into the lake. After the rock hits the surface of the lake, the rock's distance from the lake's surface changes at a rate of -5 inches per second. If lisa holds her hand 5 feet above the lake's surface, how far from Lisa's hand is the rock 4 seconds after it hits the surface? Please show how you arrive at your answer

Answer 1

Well, it goes 5 inches per second so after 4 seconds it is 4 times 5 =20 inches under the surface,  add that to 5 feet and you get 6 ft and 8 inches