$(3)$ unsteady state Energy balanc.

$W_{in}^{}=1\frac{\text{B}\text{t}\text{u}}{sec}$

juse the energy balance to $21018I\frac{b}{h}r$

$Y=0\mathrm{.}75$

Find the temperature of exit $0,1$ as function of $.$t$.$

; how long does it take for the exit oil to rise it Temp to go $f?$

what is the maximam temp can be achieved in the tank?