
Arturo O. answered 10/19/18
Experienced Physics Teacher for Physics Tutoring
h(t) = -16t^2 + 96t
Plug in t = 4 and evaluate.
Maximum height is at the vertex of the height-vs.-time parabola, which is at
t = -96/[2(-16)] sec = ? sec
Evaluate h(t) at this value of t to get maximum height.
Since the water takes off from the ground, the total time in the air is just twice the time to maximum height.