Suppose it takes at least 5 people to push a very heavy box up a 400-cm ramp. If there are actually 6 people there to help push, which ramp(s) could they use to get the box moved? (Assume no friction)

A 200-cm ramp
B. 400-cm ramp
C. 800-cm ramp
D. Either the 400-cm ramp or the 800-cm ramp would work.

Anonzero net force acts on a particle and does work. which one of the following statements is true? the kinetic energy of the particle changes, but the speed of the particle does not change. the kinetic energy of the particle does not change, but the speed of the particle does change. the kinetic energy of the particle changes, but the velocity of the particle does not change. the kinetic energy and the speed of the particle change, but the velocity of the particle does not change. the kinetic energy, speed, and velocity of the particle change.