Air that initially occupies $\backslash (0\mathrm{.}18\backslash$mathrm$\{$~m$\}^\{3\}\backslash )$ at a gauge pressure of $72$ kPa is expanded isothermally to a pressure of $101\mathrm{.}3$ kPa and then cooled at constant pressure until it reaches its initial volume. Compute the work done by the air. $($Gauge pressure is the difference between the actual pressure and atmospheric pressure.$)$