43, 560 square feet = 1 acre A quick google search like 'acres to square feet' or 'square feet to acres' will give you the answer using the google calculator.
A bushel is a dry capacity measure. A square foot is a measure of area.Without further information a meaningful answer to this question cannot be provided.
21 780 sq feet
To a greater accuracy than scientifically reasonable
Given that only one significant figure is in the question a proper answer would be:
2 * 105 square feet