Answer: D. 1.4 meters/second
Step-by-step explanation:
To calculate average Velocity, the proportion of the total Displacement or distance traveled to the total time taken during that Displacement is calculated.
Total Displacement from rest(that is 0) to 15 seconds (21, on the graph)
(0, 21)
Total time taken = 15 seconds
Average Velocity = (total Displacement / total time taken)
Average Velocity = (21 - 0) / (15 - 0)
Average Velocity = 21 / 15
Average Velocity = 1.4 meters per second