An Object Is Moving in a Straight Line

Multiple Choice

An object is moving in a straight line.At t = 0,its speed is 5.0 m/s.From t = 0 to t = 4.0 s,its acceleration is 2.5 m/s².From t = 4.0 s to t = 11.0 s,its speed is constant.The average speed over the entire time interval is

A) 9.5 m/s
B) 15 m/s
C) 13 m/s
D) 21 m/s
E) 8.2 m/s