The graph shows a car's velocity over time. Velocity versus Time
60
50
40
Velocity (mph)
30
20
10
2
6
7
3 4 5
Time (s)
What is the car's acceleration between 6 and 7 seconds?
O
A. 9 mph/s
B. 12.5 mph/s
C. 7.5 mph/s
D. 60 mph/s