A Small Car Meshes with a Large Truck in a Head-On

Multiple Choice

A small car meshes with a large truck in a head-on collision.Which of the following statements concerning the momentum during the collision are correct? (There could be more than one correct choice.)

A) The momentum of the truck is constant.
B) The momentum of the car is constant.
C) The car and the truck must undergo the same change in speed.
D) The momentum of the car and the momentum of the truck are each constant.
E) The momentum of the car-truck system is constant, but the momentum of each one separately is not constant.