Atennis player moves in a straight-line path as shown in the figure below. find her average velocity in the following time intervals.

To find the average velocity in a velocity-time graph at a particular interval, simply determine the gradient at that particular interval. 

a. average velocity= 4/1 
= 4m/s 

b. average velocity from 1 to 2.5s= 6/(2.5-1) 
= 4m/s 

average velocity from 2.5 to 4.0s= 0m/s 

average velocity from 0 to 4.0s= (4+0)/4 
= 1m/s 

c. average velocity from 1.0 to 4.0s= (4/3)m/s 

average velocity from 4.0 to 5.0s= 2/1 
= 2.0m/s 

average velocity from 1.0 to 5.0s= ((4/3)+2)/4 
= (5/6)m/s 

d. average velocity from 0 to 4.0s= 1.0m/s 

average velocity from 4.0 to 5.0s= 2.0m/s 

average velocity from 0 to 5.0s= (1.0+2.0)/5 
= (3/5)m/s