Calculus Speed/Velocity

Question

If a construction worker drops a wrench from the top of a building 500 feet high the wrench will be

s(t) = -16t^2 + 500

above the ground after t seconds. What is the speed of the wrench 5 seconds after it was dropped. Answer in units of ft/sec.

Answer 1

you need to take the derivative to get velocity

s prime = -32t

solve for s prime when t is five

-32(5) = -160