The answer
is 85 gallons
in a day
Answer: 
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Explanation:
Point-slope form is
where m is the slope and 
is the point the line goes through.
We're given the slope of m = 5/6, and we want the line going through (-8,0) which is the x-intercept -8. The x-intercept always occurs when y = 0.
So,
We can replace the y-0 with y; however, I'm going to keep that 0 so that the equation better matches the point-slope form.
y=-4x+7
the -4 is the slope and the 7 is the y-intercept
I'm thinking n would be -2 but when I add it stops at 11 and when I put -3 in its place it says 14 so I'm guessing maybe -2.4
Put numbers in order: 4,5,6,6,7,8,9,9,10,10,12,12,14,15
Cut the list into two equal parts: 4,5,6,6,7,8,9 and 9,10,10,12,12,14,15
Find middle numbers: 4,5,6,6,7,8,9 and 9,10,10,12,12,14,15
Lower quartile: 6
Upper quartile: 12
The difference of the values of the first and third quartiles of the data set is 12 - 6 = 6
