The human body must maintain its core temperature inside a rather narrow range around 37°C. Metabolic processes, notably muscular exertion, convert chemical energy into internal energy deep in the interior. From the interior, energy must flow out to the skin orlungs to be expelled to the environment. During moderate exercise,an 80 kg man can metabolize food energy at the rate 300 kcal/h, do60 kcal/h of mechanical work, and put out the remaining 240 kcal/hof energy by heat. Most of the energy is carried from the body interior out to the skin by forced convection (as a plumber wouldsay), whereby blood is warmed in the interior and then cooled atthe skin, which is a few degrees cooler than the body core. Without blood flow, living tissue is a good thermal insulator, with thermalconductivity about 0.210 W/m·°C. Show that blood flow isessential to cool the man's body by calculating the rate of energyconduction in kcal/h through the tissue layer under his skin. Assume that its area is 1.20m2, its thickness is 2.50 cm, and it is maintained at37.0°C on one side and at 34.0°C on the other side.