Answer:
See explanation and image attached
Step-by-step explanation:
Acceleration refers to the rate of change of speed with time. We can see that between 0 and 4.7 seconds he accelerated quickly . That means that the rate of change of speed with time was greatest between 0 and 4.7 seconds.
A graph of the motion is shown in the image attached. We can see that he maintained a constant speed after 4.7 seconds.
