Problem 67 Bob and Kathy, two construction workers on the roof of a building, are about to raise a keg of nails from the ground by means of a light rope passing over a light frictionless pulley 10.0 m above the ground. Bob weighs 900 N, Kathy 600 N, the keg 300 N, and the nails 600 N. Both workers slip off the roof, and the following unfortunate sequence of events takes place. Hanging together on the rope, Bob and Kathy strike the ground just as the keg hits the pulley. Unnerved by his fall, Bob…