$4\mathrm{.}57$ C Figure $P4\mathrm{.}57$ provides steady$-$state operating data for a

parallel flow heat exchanger in which there are separate streams of

air and water. Each stream experiences no significant change in pres$-$

sure. Stray heat transfer with the surroundings of the heat exchanger

and kinetic and potential energy effects can be ignored. The ideal gas

model applies to the air. If each stream exits at the same temperature,

determine the value of that temperature, in K $.$