Consider one dimensional steady state heat conduction across a wall (as shown in figure below) of thickness $30$ $mm$ and thermal conductivity $15$ $W/m.K$. At $x$ = $0$, a constant heat flux, ${q}''$ = $1×105$ $W$/$m^2$ is applied. On the other side of the wall, heat is removed from the wall by convection with a fluid at $25^0C$ and heat transfer coefficient of $250$ $W$/$m^2.K$. The temperature (in $°C$), at $x$ = $0$ is _______