A ball is thrown straight upwards from the roof of a tall building. The building is 60.0 m high. A physics student in a window 25.0 m from the ground records the ball as it passes-by to be moving with a downward speed of 28.5 m/s.
a) Determine the total time it takes the ball to hit the ground after it is thrown.
b) Determine the velocity of the ball right before it hits the ground.