For each Y value, the cross section of the solid taken perpendicular to the Y axis is a rectangle whose base lies in R and whose height is Y. Express the volume of the solid with a definite integral. So pause this video and see if you can do that. All right, now let's do this together. And first let's just try to visualize the solid. And I'll try to do it by drawing this with a little bit of perspective. So if that's our Y axis, and then this is our X axis right over here.