Problem $2$: Application of PREOS part $2$

Carbon dioxide at $40$ bar and $170C$ expands adiabatically and irreversibly in a piston$-$cylinder to $1$ bar pressure; the external pressure during the expansion is $3$ bar.

a$)$ Use the Peng$-$Robinson EOS to determine how much work was done. Provide a screenshot of the solution with your name$($s$)$ on Cell A$5.$

b$)$ What is the final temperature of the system?

c$)$ What is the entropy change of the system in this process?