A ballet student with her arms and a leg extended spins with an initial rotational speed of .80 rev/s. as she draws her arms and leg towards her...

A ballet student with her arms and a leg extended spins with an initial rotational speed of .80 rev/s. as she draws her arms and leg towards her body, her rotational inertia becomes .80 kg*m^2, and her rotational velocity is 4.1 rev/s. Determine her initial rotational inertia. Covert from rev/s to rad/s.