A hot steam pipe having an inside surface temperature of 250C has an inside diameter of 8

Question:

A hot steam pipe having an inside surface temperature of 250ºC has an inside diameter of 8 cm and a wall thickness of 5.5 mm. It is covered with a 9-cm layer of insulation having k = 0.5 W/m ∙ ºC, followed by a 4-cm layer of insulation having k = 0.25W/m ∙ ºC. The outside temperature of the insulation is 20ºC. Calculate the heat lost per meter of length. Assume k = 47 W/m ∙ ºC for the pipe.