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Steam at 400°F flows through a 2-in (ID) copper pipe having a thickness of 0.25 in. The outside surface of the pipe is insulated with 1-in-thick layer of fiberglass and 0.008-in-thick layer of aluminum. The outside surface of the insulation is exposed to air at 80°F. The convection coefficients for steam and air are 25 and 12 Btu/h-ft2 -°F, respectively. The thermal conductivity of fiberglass is 0.022 Btu/h-ft-°F. Conductivities of metals may be taken from Geankoplis. a. Calculate the rate of heat transfer for 30-ft length of the pipe in Btu/h. b. What are the interface and surface temperatures? c. Calculate the overall heat-transfer coefficient based on the outside pipe area