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On an average winter day (3 or 38 ) in a typical house, energyalready in the house is lost at the following rates: (i) 2.1 islost through partially insulated walls and the roof by conduction;(ii) 0.3 is lost through the floor by conduction; and (iii) 1.9 islost by conduction through the windows. Additional heating is alsoneeded at the following rates: (iv) 2.3 to heat the airinfiltrating the house through cracks, flues, and other openingsand (v) 1.1 to humidify the incoming air (because warm air mustcontain more water vapor than cold air for people to becomfortable). On the same day in the same house some thermal energyis supplied by heating in the following amounts: (i) sunlightthrough windows, 0.5 ; (ii) thermal energy given off by theinhabitants, 0.2 ; and (iii) thermal energy from appliances, 1.2.

Part A Suppose that the following design changes are made to the housedescribed above: (i) additional insulation of walls, roof, andfloors, cutting thermal losses by 60 ; (ii) tightly fitting double-glazed windows with selective coatings to reduce the passage ofinfrared light, cutting conduction losses by 70 ; and (iii)elimination of cracks, closing of flues, and so on, cuttinginfiltration losses by 70 . What is the total rate at which energyis lost from this house? Express your answer to two significant figures andinclude the appropriate units. ANSWER: = -2.6 Please show how to get to answer per professor answer is -2.6kW