A Car of Mass 1689 Kg Collides Head-On with a Parked

Multiple Choice

A car of mass 1689 kg collides head-on with a parked truck of mass 2000 kg.Spring mounted bumpers ensure that the collision is essentially elastic.If the velocity of the truck is (in the same direction as the car's initial velocity) after the collision,what was the initial speed of the car?

A) 19 km/h
B) 38 km/h
C) 29 km/h
D) 10 km/h