A Tennis Ball Is Shot Vertically Upward in an Evacuated

Multiple Choice

A tennis ball is shot vertically upward in an evacuated chamber inside a tower with an initial speed of 20.0 m/s at time t = 0 s.
-What is the magnitude of the acceleration of the ball when it is at its highest point?

A) zero m/s²
B) 9.80 m/s²
C) 19.6 m/s²
D) 4.90 m/s²
E) 3.13 m/s²