$-1\mathrm{.}17kJ$;$-1\mathrm{.}91kJ$

$5\mathrm{.}15$ Two cubic metres of helium at a pressure of $150$ kPa and a temperature of $22C$ is

compressed isothermally through a volume ratio of $4$:$1.$ If the adiabatic index for helium

is $1\mathrm{.}67,$ determine:

$($a$)$ the specific heat capacity at constant pressure and constant volume;

$($b$)$ the mass of helium;

$($c$)$ the final pressure:

$($d$)$ the work done;

$($e$)$ the beat flow:

$($f$)$ the change in internal energy;

$($g$)$ the change in eathalpy.