A5-cm-diameter steel pipe is covered with a 1-cm layer of insulating material having k = 0.22 W/m · ºC followed by a 3-cm-thick layer of another insulating material having k = 0.06 W/m · ºC. The entire assembly is exposed to a convection surrounding condition of h = 60 W/m2 · ºC and T∞ = 15ºC. The outside surface temperature of the steel pipe is 400ºC. Calculate the heat lost by the pipe-insulation assembly for a pipe length of 20 m. Express in Watts.