The height of a ball (in feet) t seconds after it is thrown is given by h(t)= -16t^2+ 38t + 74; its (upward) velocity at time t is v(t)= -32t + 38.

(a) From what height was the ball thrown?

(b) What was the ball's initial velocity? Was it thrown up or down? How can you tell?

(c) Was the ball's height increasing or decreasing at time t=2?

(d) At what time did the ball reach its maximum height? How high was it then?

(e) How long was the ball in the air?

My answers

(a) 96 feet (I plotted it on a graph)

(b) 74mph, the ball was thrown up because the velocity is a large number

(c) The ball's height was increasing

(d) At t=1 it was 96 feet

(e) 6 minute

Are these correct?