A model rocket is fired vertically from rest. It has a net acceleration of 17.5 m/s2. After

Question:

A model rocket is fired vertically from rest. It has a net acceleration of 17.5 m/s2. After 1.5 s, its fuel is exhausted and its only acceleration is that due to gravity.
(a) Ignoring air resistance, how high does the rocket travel?
(b) How long after liftoff does the rocket return to the ground?