Chapter 11, Problem 69P

A gymnast does cartwheels along the floor and then launches herself into the air and executes several flips in a tuck while she is airborne. If her moment of inertia when executing the cartwheels is $13.5 \text{kg}\cdot {\text{m}}^{\text{2}}$ and her spin rate is 0.5 rev/s, how many revolutions does she do in the air if her moment of inertia in the tuck is $3.4 \text{kg}\cdot {\text{m}}^{\text{2}}$ and she has 2.0 s to do the flips in the air?