At the end of shift, you decide to use the dilution ventilation system at your facility to purge airborne contaminant so that the workers of next shift will not be over-exposed. The ventilation system has a capacity to run at 8 air changes per hour. Please determine how long (in minutes) will it take the ventilation system to remove 95% airborne contaminants (assuming not new contaminants will be generated during the purge process, and perfect mixing mi=1). Please look at the CDC example I discussed. You need to include what equation you use