Arightward-moving truck skids to a stop from a very high speed with its wheels locked. what forces are exerted on the object?

Answer

Friction between the wheels and the ground, normal force, and friction force in the brakes.

Explanation

A truck moves on the surface simply because the driving force is greater than frictional force. The is always the normal force acting perpendicularly on the ground. The frictional force will be applying in two areas that is in the brakes and between the road and the wheels.

So, the forces exerted on the object are; friction and the normal force.