I swear, this is the last problem that I have. Here it goes... A pool ball having a mass of .65 kg experiences an elastic collision with a croquet ball having a mass of 1.38 kg. The pool ball had been rolling for 4.3 seconds, having covered a distance of 22.6 meters during that time. The croquet ball had been struck by a mallet only .80 seconds before the collision, and was given an acceleration of 12.6 m/s^2. How far from the point of impact will the pool ball be 1.9 seconds after the collision? I'm lost on how to start the problem. I am sorta confused on how to solve for the displacement when not given the velocity/acceleration of both objects. I know that there's a way to get around that, but I can't see it. Can someone point out a formula that would help me solve this freakishly annoying problem.