How many gallons of liquid in a 5foot by 6foot by 3.5 foot tank
Your tank has a capacity of 5.0' x 6,0' x 3.5' = 105.0 cubic feet.
Next, you have to know how many gallons are in a cubic foot.
This isn't something you know intuitively, you have to look it up.
Here you go: 7.48052 gal / ft3 x 105.0 ft3 = 785.5 gal (rounded)
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