A small car collides with a large truck.
(a) Is the magnitude of the force experienced by the car greater than, less than, or equal to the magnitude of the force experienced by the truck?
(b) Choose the best explanation from among the following:
I. Action-reaction forces always have equal magnitude.
II. The truck has more mass, and hence the force exerted on it is greater.
III. The massive truck exerts a greater force on the lightweight car.