A figure skater spins with her arms outstretched with an angular speed of =rev/s (left figure).

The moment of inertia with her arms outstretched is I_{1}=kg m^{2}.
She then pulls their arms in, as shown in the right figure, decreasing her moment of inertia
to I_{2}=kg m^{2}.
What is the skater's new rate of rotation?