3-18E Consider an electrically heated brick house (k = 0.40 Btu/h ft-°F) whose walls are 9 ft high and 1 ft thick. Two of the walls of the house are 50 ft long and the others are 35 ft long. The house is maintained at 70°F at all times while the temperature of the outdoors varies. On a certain day, the temperature of the inner surface of the walls is measured to be at 55°F while the average temperature of the outer surface is observed to remain at 45°F during the day for 10 h and at 35°F at night for 14 h. Determine the amount of heat lost from the house that day. Also determine the cost of that heat loss to the homeowner for an electricity price of $0.09/kWh. FIGURE P3-18E 9 ft TiD=70°F 50 ft 35 ft

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Please help with assumptions and fbd

A house has a three meter deep basement (foundation) wall that is in a 10 meter by eight meter rectangular shape based on interior dimensions. On average, 2.5 meters of the wall is below grade. Assume the outside air temperature is 38°C and the inside temperature is 20°C; there is an average ground temperature of 27°C. Determine the rate of heat loss through the wall if it is insulated with an R-value of about 30°C.m^2/W.