For the spring-mass-damper system shown to the right, r is measured from the static equi- librium position. If the coefficient of friction is p a) determine the governing equations of motion: b) if the system is released from rest with 2(0)=20 > 0, what is the minimum value of ro so that the block slips; c) find the range of initial displacements so that the system comes to rest after one complete cycle. ww 6 k m ww 2 k