Estimate the number of occupants that are seated in an occupied university lecture hall if the room has a floor area of 175 m2, a ceiling height of 4 m, a constant ventilation rate of 1.5 per hour, and the room achieves a steady-state indoor co2 concentration of 1200 ppm. you can assume:
1) the indoor temperature is 22°c;
2) the outdoor co2 concentration is 400 ppm;
3) the building is at sea level;
4) the average per-person co2 emission rate is 21 g/hr;
5) the room is well-mixed; and
6) the ventilation rate, outdoor co2 concentration, occupancy, and indoor emissions are all constant.