An engineering student is testing the acceleration of an electric prototype kart along a straight horizontal track.
The student plotted the velocity of the kart against time on the graph shown below, but the recording software stopped logging data after 6 seconds6\text{ seconds}6 seconds.
Assuming the kart continues to accelerate at the same constant rate, estimate the velocity of the kart at time t=9 secondst = 9\text{ seconds}t=9 seconds.
Show how you obtain your answer.