$5\mathrm{.}3$ A Carnot heat engine using air as working fluid receives $175kJ$ of heat from a high temperature reservoir and rejects $70kJ$ of heat to a low temperature reservoir. The pressure after isothermal expansion is $280$kPa. If the maximum molar volume in the cycle is $0\mathrm{.}18\frac{m^3}{m}ol,$ calculate the high and low reservoir temperatures.

$($Answer: $613\mathrm{.}3K$ and $245\mathrm{.}3K)$