A panicle of mass 11/ is in the lowest energy (ground) state of the in fi nite potential energy well VCr) = {o 0 < x < L . 00 elsewhere At time I = 0 the wall located at x = L is suddenly pulled back to a position at x = 2L. This change occurs so rapidly that instantaneously the wave function does not change. (a) Calculate the probability that a measurement of the energy will yield the ground-state energy of the new well . What is the probability that a measurement of the energy will yield the first excited energy of the new well? (b) Describe the procedure you would use to determine the time development of the system. Is the system in a stationary state?