Prb$.2(60$ p$)-$ Air enters a nozzle steadily at

$280$kPa and $778C$ with a velocity of $50\frac{m}{s}$

and exits at $85$kPa and $320\frac{m}{s}.$ The heat

loss from the nozzle to the surrounding

medium is estimated to be $3\mathrm{.}2k\frac{J}{k}g.$

Determine;

$($a$)$ The exit temperature, $C.$

$($b$)$ Entropy change of the air between inlet and

outlet condition, in $k\frac{J}{k}g-K.$