A piston/cylinder contains 4 lbm of air at 100 F, 2 atm. The piston is loaded with a linear spring, mass, and the atmosphere. Stops are mounted so that V stop 100 ft3, at which point P 6 atm is required to balance the piston forces. The air is now heated to a final pressure of 60 lbf/in 2. Find the final temperature, volume, and the work and heat transfer. Find the work done on the spring.