A young boy of mass Mb is terrorizing his sister (mass Mg) riding on a frictionless bearing merry-go-round (mass Mr) that has centroidal mass moment of inertia I*=(1/2)Mr(R^2). The boy runs back and forth to the center of the merry-go-round from the edge at radius R opposite the girl, completing one circuit in 2 seconds. What is the acceleration the girl experiences as she clings to the outer edge (at R) of the handle bars? The initial angular speed of the merry-go-round is (omega_0).