



 
Thom, There are 231 cubic inches in an American gallon and an acre is 43560 square feet. You need to decide whether to work in inches or feet. I am going to use inches. There are 12 inches in a foot so 12 × 12 = 144 square inches in a square foot. Thus an acre is 43560 × 144 square inches. Multiply this by 0.25 inches to determine the number of cubic inches in 1 acre of water 0.25 inches deep. Divide this by 231 to determine the number of gallons. Penny  


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