The minimum fresh air requirement of a residential building is specified to be 0.35 air changes per hour (ashrae, standard 62, 1989). that is, 35 percent of the entire air contained in a residence should be replaced by fresh outdoor air every hour. if the ventilation requirement of a 2.7-m-high, 200-m2 residence is to be met entirely by a fan, determine the flow capacity in l/min of the fan that needs to be installed. also determine the minimum diameter of the duct if the average air velocity is not to exceed 5.5 m/s.