a refrigerator uses a polyatomic gas with Cp$=7/2$r as the working fluid in a four step cycle. first, a volume of $0\mathrm{.}3$ m$^3$ at $"-10$c and $2$ atm $($state $1)$ is compressed adiabatically to one$-$fourth the original volume $($state $2).$ Second, the gas is allowed to cool under constant pressure to room temperature, $25$ C $($state $3).$ At this point, the gas condenses into a liquid..