There can be no possible answer.
An inch is a measure of length or distance in 1-dimensional space while a cubic foot is a measure of volume in 3-dimensional space. The two measure different things and, according to basic principles of dimensional analysis, any attempt at conversion from one to the other is fundamentally flawed.
253 feet
20 cu feet
253 L x 1000 = mL, 1 mL = 1cm^3 --> 253,000cm^3 divided by 100= cm^3 for every m^3 divide 2530 by the number of feet in a meter (i.e. 3 feet) = 843.33 cubic feet
6,084*pi cubic feet or about 21,364.56 cubic feet.
300 feet.
4x4x3 = 48 cubic feet
0.135 cubic feet
No-one knows.
36
2 feet
A man who is 60 cubits tall is 90 feet tall!
The units are not dimensionally equivalent. The first (1.25 sq ft) is area, which is 2 dimensional. The second (8 cubic feet) is volume, which is 3 dimensional. Now you could have a box, which has a 1.25 square foot base, and is 6.4 feet tall, and that box would have a volume of 8 cubic feet.