5280 ft = one mile
529/5280 = 0.1002 miles, or about one tenth mile
528 ft = 0.1 mile, exactly
There are 5280 feet in one mile. Therefore, 529 feet is equal to 529/5280 = 0.1001893 recurring (that is, 0.10018939393..) miles.
529 square feet is 49.1457 square meters.
529 square feet = 49.15 square meters.
529 sq m = 5694.11 sq feet (to 2 dp)
The perimeter is 92 feet.
It is: 23 times 23 = 529 square feet
529
529.
A LINEAR foot can be considered to have either 0 or infinite width so either no matter how many you have you'll never cover 529 SQUARE feet, or such an infinitely small (as near to nothing as makes no odds) amount of them are needed.
Square root 529 which is 23 m
$2
The requirement for the 529 plan, for residents of Illinois, would be of course residence, and then you would need various proof of living and birth to show.