A student sits at rest on a piano stool that can rotate without friction. the moment of inertia of the student-stool system is 4.1 kg·m2. a second student tosses a 1.5 kg mass with a speed of 2.3 m/s to the student on the stool, who catches it at a distance of 0.42 m from the axis of rotation. what is the resulting angular speed of the student and the stool?