Two rowers on the opposite shores of a lake start moving towards each other. When they pass each other they are 600 yards from one shoreline. They each continue to the opposite shore, immediately turn around and start back. When they meet again they are 200 yards from the other shoreline. Each rower maintains a constant speed throughout. How wide is the lake? 作者: 克里斯蒂 时间: 2009-10-20 12:25