Answer: B) 4 BTUs/ft^3
Step-by-step:
For a cuboid of length L, width W and height H, the volume is:
V = L*W*H
In this case, we have:
L = 20ft
W = 15ft
H = 10ft
Then the volume of the room is:
V = 20ft*15ft*10ft = 3000 ft^3
Now we have 6 people, and each generate 400 BTUs per hour.
Then in total, they generate:
6*400 BTUs per hour
2400 BTUs per hour.
Now we want to find the BTUs per ft^3 produced in 5 hours.
Then if they generate 2400 BTUs per hour, in 5 hours they generate a total of:
5*2400 BTUs = 12000 BTUs
Now we take the quotient between the total BTUs and the volume of the room:
Q = (12000 BTUs)/(3000 ft^3) = 4 BTUs/ft^3
The correct option is B.
The answer to this question is a.
If 30% of his collection is 12 cars, then we can use the fraction
30/12=100/x
x=40
