1 kilogram = 1000 grams so 40510 kg = 40510*1000 = 40510000 grams. SImple, really!
It is 40,000 square feet.
280 square feet.
220 square feet
1,205.56 square feet.
10,763.9 square feet.
50 square feet = ~4.65 m2
1 (square meter) = 10.7639104 square feet.
1,620 square feet.
1.07474093 × 1014 square feet
150 square feet
1,350 square feet.