Atennis ball travels the length of the court in 24 m in .5 seconds find its average speed

Speed= Distance/Time
Distance=24m
Time= 5seconds
Speed= 24/5= 4.8m/s

A tennis ball travels the length of the court in 24 m in .5 seconds its average speed 
24 / 0.5 = 48 m/s

Acceleration is a vector quantity that expresses the rate of change in velocity. Being a vector quantity, then the value has magnitude and direction. If the car exerts a constant net force as it travels, the greater the angle of elevation is, the greater is the decrease in its acceleration. Since the vertical component of is affected by the acceleration due to the gravity, that is why vehicles exert more force to climb a steeper hills.