Thermo dynamic 1 problem

What is the maximum work that can be extracted per mole of gas? State all assumptions
b) Your boss tells you that the compressor is only 80% efficient, but the T and P answers above are still the same in this case as well. How is this possible? Is this scenario feasible?
A simple yes or no answer will not suffice. Rather a more detailed answer is required
c) Repeat parts (a) and (b) in the case where the fluid is