Blocks A and B of mass m are placed inside an elevator which is going upward with an acceleration of 2 m/s2 and a convex mirror having focal length 12 cm is placed below block B. All the surfaces are smooth and the pulley is light. The mass pulley system is released from rest with respect to the elevator at time t=0 s, when the distance of the block B from the mirror is 42 cm. Find the distance between the image of the block B and mirror at t=0.2 s.