Achild throws a baseball directly upward. what are the signs of the velocity and acceleration of the ball at the very top of the ball's motion (i. e., the point of maximum height)?

velocity zero and acceleration negative

Explanation:

According to the directions taken in the vector analysis, the direction which is upwards taken as positive, the direction which is downwards is taken as negative.

The direction which is rightwards taken as positive and the direction which is leftwards taken as negative.

here, ball throws vertically upwards and it attains a maximum height. At maximum height the magnitude of velocity is zero but the acceleration is always acting downwards so it is taken as negative in sign.

i would say