A single$-$stage reciprocating air compressor is required to compress $72$ m$3$ of air per

minute from $15\backslash$deg C and $1\mathrm{.}0$ bar to $8$ bar pressure. Find the temperature at the end of

compression, work done, power, and heat rejected during each of the following

processes: $($a$)$ isothermal, $($b$)$ adiabatic, and $($c$)$ polytropic compression following the law

pV$1\mathrm{.}25=$ constant.