A train is moving 35 m/s to the east. It speeds up to 42 m/s east over the
course of 40 seconds. What was the train's acceleration?
O A. 0.175 m/s2 west
O B. 5.71 m/s2 east
O C. 5.71 m/s2 west
O D. 0.175 m/s2 east