A piston - cylinder device initially contains 0.1 m^3 of nitrogen gas at 150 kPa and 130 °C. The nitrogen is now expanded polytropically to a state of 120 kPa and 115 °C. Determine the following: (a) The mass (kg) and volume (m^3) of the nitrogen at the initial state? (b) The boundary work done during the process, in kJ?