Problem $2.$ A plane wall, as shown, has a thermal conductivity

$k=1\mathrm{.}2\frac{W}{m}*K$ and a thickness $L=6cm.$ One side of the wall

is exposed to irradiation $G=3000\frac{W}{m^2},$ of which $90\%$ is

absorbed by the left surface. Both sides of the wall are subject to

convection heat transfer with air at $T_{}=25C$ and a convection

heat transfer coefficient $h=45\frac{W}{m^2}*C.$ Neglect radiative heat

transfer to the surroundings.

$($a$)$ List four assumptions for solving this problem:

$($b$)$ Draw an equivalent thermal circuit:

$($c$)$ Find the steady$-$state temperatures on each side of the wall, $T_1$ and $T_2,$ respectively.