A playground merry go round of a diameter 6.00 m and mass 240 kg is rotating at 12.0 rev/min about a frctionless vertical axle. Facing the axle, a 30....

A playground merry go round of a diameter 6.00 m and mass 240 kg is rotating at 12.0 rev/min about a frctionless vertical axle. Facing the axle, a 30.0 kg child hops on to the merry go round and manages to sit down on its ledge. What is the new angular speed of the merry go round in rad/s?