If this is the stationary wall isn’t the ANSWER that there is no work being done? If not what is the correct answer and why? Help!!

22. the effect of threshold braking is to a cause skids. b. lock wheels. c. prevent locking of wheels. d. increase stopping distance.

Two carts, one of mass 2m and one of mass m, approach each other with the same speed, v. when the carts collide, they hook together. assume that positive momentum is to the right. which graph best represents the momentum of both carts over time, before and after the collision?

Aball is thrown horizontally from a cliff at 8m/s .in what direction is the ball moving 2s later?