During strenuous work a human body generates about 2,400 BTUs of body heat per hour. If 6 football players are in a gym that is 12 ft × 18 ft × 10 ft lifting weights, how many BTUs per cubic foot do they produce in 2 hours? (to the nearest tenth)
A) 13.3 BTUs/ft^3
B) 40.0 BTUs/ft^3
C) 66.7 BTUs/ft^3
D) 133.3 BTUs/ft^3