A piston cylinder device initially contains 0.5 kg of R134a at 200 kPa and a specfic volume of 0.07 m^3/kg. At this point the piston rests on a set of stops and the mass of the piston is such that a pressure of 280 kPa is required to lift it. Heat is now slowly transferred to the refrigerant until the specific volume reaches 0.1 m^3/kg. The atmospheric pressure is 100 kPa. A.) What will the temperature of the R134a be when the piston just lifts off the stops? B.) What is the final temperature of the refrigerant? C.) What is the total change in internal energy of the refrigerant?