A 1000-Kg Automobile Moving with a Speed of 24 M/s

Multiple Choice

A 1000-kg automobile moving with a speed of 24 m/s collides with a 500-kg car initially at rest. If the two stick together, what is the velocity (in m/s) of the two cars after the collision relative to an automobile moving in the same direction at 15 m/s?

A) 14
B) 16
C) 24
D) 48
E) 1.0