A ball is dropped from the same height, but 20 feet away from the side of the building.

A light is attached to the wall of a building 64 feet abovethe ground. A ball is dropped from the same height, but 20feet away from the side of the building. The height y of theball at time t is given by y(t) = 64 − 16t2. How fast is theshadow of the ball moving along the ground after 1 second?