$(35$ points$)$: A composite wall as shown in the figure, the wall $B$ is experiencing a uniform

heat generation of $1\mathrm{.}2{10}^6\frac{W}{m^3}$ and there is no heat generation in Wall A$.$ The thermal

conductivity of wall A and wall B is $200\frac{W}{m}K$ and $100\frac{W}{m}K$ respectively. The outer

surface of the wall $A$ is exposed to atmospheric air with temperature $20C$ and heat

transfer coefficient of $250\frac{W}{m^2}K.$ The outer surface of the wall B is insulated. The

thickness of the wall A and wall $B$ is $30$ mm and $75$ mm respectively. Determine the

temperature of $T_0$ and $T_2$