On a frictionless table, a spring whose force constant is 60 nt/m has one end fixed and the other attached to mass M= 3.9 kg. A cord connects mass M to a suspended rock whose mass is m= 3.2 kg. Assume an x axis origin at the movable end of the spring when the spring contains no potential energy. At some instant, with the system stationary, the cord is cut and mass M begins simple harmonic motion.

Find the x coordinate and the velocity of the movable end of the spring exactly .60 sec after the cord is cut.