Which statement best describes how work and power are different

Aboxcar traveling at 12 m/s approaches a string of 5 identical boxcars sitting stationary on the track. the moving boxcar collides and links with the stationary cars and they all move off together along the track. what is the final speed of the cars immediately after the collision? (you may take the mass of each boxcar to be 18,537 kg.)

A2k pendulum has a speed of 1 m/s at a height of 1/2 meter

Does anyone have the answers to online physics course plato course physics, semester a v3.0