A student sits on a pivoted stool holding a pair of weights. The stool is free to rotate about a vertical axis with negligible friction. The moment of inertia of the student, weights and stool is 2.25 kg-m2. The student is set in rotation with arms outstretched, making one complete turn in 1.26 s. (a)What is the initial angular speed of the system? (b)As he rotates, he pulls the weights inward so that the new moment of inertia of the system becomes 1.8 kg-m2. What is the new angular speed? (c)Find the work done by the student on the system while pulling in the weights.