Part A
You throw a ball vertically upwards. Ignore air resistance for this problem. After you have released the ball, its acceleration is:
downward at all times except at the very top, when it is zero.
upward at all times except at the very top, when it is zero.
downward as the ball moving up and upward as the ball is moving down.
upward as the ball is moving up and downward as the ball is moving down.
upward as the ball is both moving up and moving down.
downward as the ball is both moving up and moving down.