2. A ball is thrown vertically upward from the 15m level in an elevator shaft with an initial velocity of 20 m/s. At the same instant an open-platform elevator passes the 6m level, moving upward with a constant velocity of 2 m/s. Determine

Question

a. When and where the ball will hit the elevator,
b. The relative velocity of the ball with respect to the elevator when the ball hits the elevator.