1) The two-story office building has 36,000 ft of office space. Due to cracks around windows and doors, the air leaks in on the windward side of the building and exits on the leeward side. Tests were conducted on the building for energy efficiency when the outdoor temperature was 15°F. The inside was at 70°F. The infiltration rate due to cracks was 75 ft/min and infiltration due to door openings was 50 ft/min. a) What is the volumetric flow rate of air exiting the building assuming steady state, air as an ideal gas and no significant pressure difference between the inside and outside of the building? b) Determine the number of building air volume changes per hour. c) If you need to meet the CDC guidance for airborne contaminant removal at 2 ACH, do you need to change the ventilation for the building?