Fifty-two and eighty-sixth hundredths.
<span>3 tanks because he can do 400 miles on tank, and he's goin 1,100 miles, he does 400 miles with first tank, next tank he gets to 800 miles, and then he uses 3/4 of last tank to get to 1,100, he will then have 100 miles left on the tank though.</span>
2 days to get this apology. its really does suck to not get your question answered in the firs ten min <span />
Split up the interval [2, 5] into

equally spaced subintervals, then consider the value of

at the right endpoint of each subinterval.
The length of the interval is

, so the length of each subinterval would be

. This means the first rectangle's height would be taken to be

when

, so that the height is

, and its base would have length

. So the area under

over the first subinterval is

.
Continuing in this fashion, the area under

over the

th subinterval is approximated by

, and so the Riemann approximation to the definite integral is

and its value is given exactly by taking

. So the answer is D (and the value of the integral is exactly 39).