So x has got to be between zero and 10. Otherwise, we've cut too much or we're somehow adding cardboard or something. So first let's think about the volume at the endpoints of our domain, of what x can be for our volume. Well, our volume when x is equal to zero is equal to what? We're going to have zero times all of this stuff, and it's pretty obvious. You're not going to have any height here, so you're not going to have any volume, so our volume would be zero. What is our volume when x is equal to 10?