A standard 1-in. Schedule 40 steel pipe carries saturated steam at 250°F. The pipe is lagged (insulated) with a 2-in, layer of 85 percent magnesia pipe covering, and out-side this magnesia there is a 1/2-in. layer of cork. The inside temperature of the pipe wall is 249°F, and the outside temperature of the cork is 90°F. Thermal conductivities, in Btu/ft-h- °F, are: for steel. 26: for magnesia, 0.034; for cork, 0.03. Calculate 

(a) The heat loss from 100 ft of pipe in Btu per hour,

(b) The temperatures at the boundaries between metal and magnesia and between magnesia and cork.