Answer:
5 BTUs/ft^3
Step-by-step explanation:
800 BTUs * 30 students = 24000 total BTUs combined
Volume of room = 20 feet * 20 feet * 12 feet = 4800 cubic feet
BTUs/ft^3 = 24000 BTUs / 4800 cubic feet = 5 BTUs/ft^3
So the amount of BTUs per cubic foot that were produced was 5 BTUs/ft^3