Amodel rocket is fired vertically upward from rest. its acceleration for the first three seconds is a(t) = 72t, at which time the fuel is exhausted and it becomes a freely "falling" body. sixteen seconds later, the rocket's parachute opens, and the (downward) velocity slows linearly to −28 ft/s in 5 s. the rocket then "floats" to the ground at that rate.
(a) determine the position function s and the velocity function v (for all times t).
(b1) at what time does the rocket reach its maximum height?
(b2) what is that height? (round your answer to the nearest integer.)
(c) at what time does the rocket land? (round your answer to one decimal place.)