Oh, dude, 20 times 20 equals 400. Like, it's not rocket science, but I get it, math can be a little tricky sometimes. So yeah, 20 multiplied by 20 gives you a grand total of 400. Boom, math wizard right here.
400 (20x20) square inches is 2.78 square feet.
401
20x20 = 400 2x4= 8 400/8= 50 needed
400
2x2x2x2x
20x20
1,000,000,000
400
25p
a lot
depends where u buy it?