Answer:
$625,000
Explanation:
The maximum revenue will be found where the derivative of the revenue function is zero.
r'(x) = 50 -2x = 0
50 = 2x
x = 25
When 2500 gallons are sold, the revenue is ...
r(25) = 50(25) -25(25) = (50 -25)(25) = 25(25) = 625 . . . thousands
The maximum revenue is $625,000.