So how do we find the volume? Well, once again, if we know the surface, if we know the area of the face of this washer, we can just multiply that times the depth. So it's gonna be the area of the face of the washer. So the area of the face of the washer, well, it could be the area if it wasn't gutted out, and what would that area be? Well, it would be pi times the overall, the outside radius squared. It would be pi times the outside radius squared. Well, what's the outside radius?