Two small marbles, A and B, move in a clockwise direction in concentric circular grooves of radii 0.2 m and 0.3 m, respectively, on a smooth horizontal table. The mass of A is 0.02 kg and the mass of B is 0.03 kg. The speed of A in its groove is 0.2 ms - and that of B is 0.9 ms -. Calculate: (a) the angular velocity of B; (b) the total moment of inertia about the axis of rotation; (c) the total moment of inertia about a parallel axis shifted by 0.3 m; (d) the centripetal force required to keep A in its groove; (e) the net torque on B. At a given instant, the marbles are 0.1 m apart. Calculate the time taken for them to be 0.5 m apart. [4]