Then the design thickness (in meter) of the wall to maintain a steady heat flux of 2500 W/m2 should be _____

Question

A plane wall has a thermal conductivity of 1.15 w/M.K. If the inner surface is at 1100⁰C and the outer surface is at 350⁰, then the design thickness (in meter) of the wall to maintain a steady heat flux of 2500 W/m² should be _________