$1.[-/14\mathrm{.}28$ Points$]$

Consider the following figure.

$\backslash [$

P$(\backslash$mathrm$\{$MPa$\})$

$\backslash ]$

$($a$)$ Determine the work done on a fluid that expands from $\backslash ($ i $\backslash )$ to $\backslash ($ f $\backslash )$ as indicated in the figure.

MJ

$($b$)$ How much work is done on the fluid if it is compressed from $\backslash ($ f $\backslash )$ to $\backslash ($ i $\backslash )$ along the same path?