You indicated that the angle between the velocity and acceleration at point D is acute but not 0�.� An acute angle bigger than 0� indicates that the ball is speeding up and following a curved path.� Is the ball speeding up at point D?

In addition, remember that at point D the ball is flying through a vacuum.� Hence, the acceleration of the ball at point D is the freefall acceleration (i.e., the acceleration of gravity).� In what direction is the freefall acceleration?

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