Car 1 of mass m1 is waiting at a traffic light.
Car 1 is struck from behind by Car 2 of mass m2.
The two cars stick together after the collision.
Car 2 was traveling at v2i = 30.0 m/s before the collision.

What is the kinetic, in [J], of the system after the collision if m1 = 2500 kg and m2 = 1000 kg?