Assume that 80% of the food calories consumed by a person is radiated as heat; the rest goes to mechanical energy. A 1.88-m (6 ft 2 in.) man has a mass of 81 kg, a body surface area of 1.8 m, and a skin temperature of 36.9 C. You model his emissivity e to be 1 because his body radiates almost entirely infrared energy, which is not affected by skin pigment. In addition, your model assumes that he loses heat only through radiation. According to your model, how many food calories should he eat per day to keep his body temperature constant in a room at 20.0 C. (Careful: The environment also radiates back into his body. The net rate of radiation is Pnet = Pbody - Penvironment.) food calories per day Does your model produce a reasonable answer? Yes = No C/day Calculate the coefficient of linear expansion a for a 14.0 m metal bar that shortens by 0.900 cm when the temperature drops from 24.0 C to 9.00 C. = 10-6 K-1