Answer to Question #15274 in Mechanics | Relativity for mace

Question

A rocket is fired vertically upward from a well. a catapult gives it initial velocity 80.0m/s at ground level. its engines then fire and it accelerates upward at 4.00m/s2 until it reaches an altitude of 1000 m. at that point its engines fail and the rocket goes into free fall with an acceleration of -9.80 m/s2. A) how long is the rocket in motion above the ground? what is the maximum altitude? what is its velocity just before it collides with the earth?