Answer:
The volume is:
Step-by-step explanation:
See the sketch of the region in the attached graph.
We set the integral using washer method:
Notice here the radius of the washer is the difference of the given curves:
So the integral becomes:
We solve it:
Factor
out and distribute the exponent (you can use FOIL):
Notice:
So the integral becomes:
Then using the basic rule to evaluate the integral:
Simplifying a bit:
Then plugging the limits of the integral:
Taking the root (rational exponents):
Then doing those arithmetic computations we get:
Answer:
I think it's D
Step-by-step explanation:
24 bottles @ $3 = 8 bottles per dollar
12.5 cents per bottle
36 bottles @ $4 = 9 bottles per dollar
11.1 cents per bottle