What nation was forced by allied forces to make reparations?

Which of the following is not am example of a polymer? protein nylon kevlar concreta

Ahockey player of mass 82 kg is traveling north with a velocity of 4.1 meters per second he collides with the 76 kg player traveling east at 3.4 meters per second if the two players locked together momentarily in what direction will they be going immediately after the collision how fast will they be moving

What is the efficiency of an engine that does 80 j of work and exhausts 320 j of heat while taking in 400 j of heat ? a. 10% b. 20% c. 80% d. 25%