A square uniform raft, 20 {rm m} by 20 {rm m}, of mass 7050 {rm kg}, is used as a ferryboat. If three cars, each of mass 1000 {rm kg}, occupy the NE, SE, and SW corners, determine the coordinates of the {rm CM} of the loaded ferryboat relative to the center of the raft. Take the origin to be at the {rm CM} of the raft.