The kitchen, bath, and other ventilation fans in a house should be used sparingly since these fans can discharge a houseful of warmed or cooled air in just one hour. Consider at 200 m2 house whose ceiling is 2.8 m. The house is heated by a 96%efficiency gas heater and is maintained at 22 ° Cand 92 kPa. Assume the average outdoor temperature during the heating season to be 5°C.If the unit cost of natural gas is $1.20/therm (1therm = 105,500 kJ), determine the cost of energy "vented out" by the fans in 1 hour. $1.20O $0.29O $2.99O $0.12

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