Answer:


Step-by-step explanation:
v = Final velocity
u = Initial velocity
a = Acceleration
t = Time
s = Displacement
Here the kinematic equations of motion are used

Time the car is at constant velocity is 39 s
Time the car is decelerating is 5 s
Total time the car is in motion is

Distance traveled




The total displacement of the car is

Average velocity is given by

The average velocity of the car is
.