The rectangular wall has been thickness $4$L and also has internal heat sources whose strength a veries according to g$=$go sin$($ax$).$ Where go is the heat generated per unit volume at the center of the wall at X$=0,$ and a is constant. If both sides of the rectangular wall are maintained at constant temperature of $($TW$).$ The rectangular wall is constructed of a material having a thermal conductivity that varies as the square of the temperature according to the relation $[$k$=$ko$(1+$T$2].$ Derive an expression for the total heat loss from the wall per unit surface area $?$

clearly solve please