5. (6 marks) Continuous infiltration rate of a building is estimated to be 20 L/s. The average winter temperature is 5 C, while air inside of the building is always maintained at 22C. The building is heated by electricity whose unit cost is $0.09/kWh. Determine the amount and cost of the heat lost as a result of infiltration per month in winter. (The gas constant and specific heat of air are R = 287 J/kg-K and cp-1.0 kJ/kg-K. Consider air at P = 100 kPa. and T=22 C)