depends how much you fill it up
We can't be sure - we need another dimension. If the Pool is 20 feet long by 48 feet wide, we need to know how deep it is - a 2 foot deep pool will not hold as much as a 10 foot deep pool. If the pool is not a uniform depth, there are formulae used to determin how much water the pool will hold. Try calling Anthony. Or Esther Williams.
1440 cubic feet of water
It depends on how long the pool is.
I do not have any water in your pool. You may have some but not me!
48 what deep? Inches, miles, etc.
You need more information. But, let's assume the pool is 8 feet deep at the deep end and 3 feet at the shallow end. If the pool is rectangular, the total volume will be 28,798 gallons of water.
About 6,042 gallons of water.
It is unlikely that the pool is 48 feet deep but there is no indication as to what units the depth is measured in. Consequently it is not possible to answer the question.
to calculate the content of the pool go to this link
About 3,758 gallons.
The swimming pool in Beijing Water cube is 13 metres deep