A small rubber ball is launched by a compressed-air cannon from ground level with an initial speed of 19.9 m/s directly upward. Choose upward as the positive direction in your analysis.
(a) What is the maximum height above the ground that the ball reaches?
(b) How long does it take to reach the maximum height?
(c) How long does it take to reach the ground after it reaches its highest point?
(d) What is its velocity just before it hits the ground? (Indicate the direction with the sign of your answer.)