A 15 kg child sits on the edge of at 2 m radius, 200 kg merry go round. A father as been getting a little carried away and has pushed it up to a tangential velocity of 8.0 m/s. With no harm being done, the child jumps off with a tangential velocity of -8.0 m/s so that he lands straight in the arms of his father (effectively giving him no angular momentum). What is the final angular velocity of the merry go round?