A piston - cylinder device initially contains 2 L of air at 100 kPa and 25C. Air

Question:

A piston - cylinder device initially contains 2 L of air at 100 kPa and 25°C. Air is now compressed to a final state of 600 kPa and 150°C. The useful work input is 1.2 kJ. Assuming
The surroundings are at 100 kPa and 25°C, determine
(a) The exergy of the air at the initial and the final states,
(b) The minimum work that must be supplied to accomplish this compression process, and (c) The second-law efficiency of this process.