7. The base of a record player is a disk that has a mass of 2 kg and a diameter of 34 cm. A child spins it so it rotates at a constant rate of 50 times a minute. Neglect friction and all that stuff that complicates problems! Then, the child drops on a record (also a disk) with mass 1.3 kg and a diameter of 32 cm. How many times a minute will they spin together if the record player base and the record stick together (assume there is no slipping when the record lands on the base)? Remember, for a solid disk or cylinder, I = 2 MR.