The figure shows an overhead view of a ring that can rotate about its center like a merry-go-round. It’s outer edge radius R_2 is 0.6 m, its inner radius R_1 is half of R_2, its mass M is 7.2kg, and mass of crossbars is negligible. It initially rotates at an angular speed of 7.4 rad/s with a cat of mass m=M/4 on its outer edge, at radius R_2. By how much does the cat increase the kinetic energy of the cat-ring system if the cat crawls to the inner edge, at radius R_1?