* EST House ventilation For purposes of ventilation, the inside air in a home should be replaced with outside air once every 2 hours. This air infiltration occurs naturally by leakage through tiny cracks around doors and windows, even in well-caulked and weather-stripped homes. (a) Estimate the mass of air lost every 2 h and each second (b) Estimate the energy per second needed to warm outside air leaking into the house during a winter night State your assumptions.
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