Bumper car A (281 kg) moving +2.81 m/s makes an elastic collision with Bumper car B (209 kg) moving +1.72 m/s. What is the velocity of car A after the collision?

Asatellite component is in the shape of a cube with 10cm edges, has an evenly distributed mass of 2 kg and one bolt hole at each of four corners. if the maximum predicted random vibration environment is 10 grms, what bolt size would be a good choice for restraint? what other factors might drive bolt size besides force/stress?