We have to determine if we can conclude anything about the work done when the system reversible changes back in forth between states 1 and 2.
To solve this problem, we need to be first aware of what state functions and path functions are.
State functions are those properties whose value does not depend upon the path taken to reach that value.
The value of a state function depends only upon the initial and final state of a system.
A mnemonic to remember state functions is: PVT HUGS
These represent pressure (P), volume (V), temperature (T), enthalpy (H), internal energy (U), Gibbs free energy (G) and entropy (S).