0.001704.
The question is meaningless. Nine feet is a linear measure - a length. Square feet is a measure of area, not length.
There are 5280 feet in one mile. Therefore, 8000 feet is equal to 8000 / 5280 = 1 mile 2720 feet.
Four miles is four miles and 0 feet.
0 miles and 2041 ft because there is 5280 feet in a mile