Number 9 please. I need help
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(1/12)X = 6800
6800/ (1/12) = X
X = 81600 (hours)
6800 (6.8 * 10^3) divided by 1/12 (12^-1) equals 81600. It will take 81600 hours for the pool to completely empty at a rate of 0.833333333 or 12^-1 gallons per second.