Respuesta :
This is a kinematics problem. But, since the rocket's velocity is asked at the highest point, it will be 0m/s because it comes to a stop for a fraction of a second. The answer is b.
Answer: 0 m/s
The rocket is launched straight upward with a velocity of 90 m/s, At the highest point, the instantaneous velocity would be 0 m/s. The rocket slows down while moving up. The velocity would be 0 m/s at the highest point for an instant and then reverses direction to return on Earth. If it is not controlled, then it would free fall under gravity.