1. The problem asks whether to use the washer or disk method for finding volumes of solids of revolution. 2. The disk method is used when the solid is formed by revolving a region around an axis and the cross sections perpendicular to the axis are disks (circles without holes). 3. The washer method is used when the cross sections are washers, meaning disks with holes, which happens when there is an inner radius and an outer radius. 4. To decide which method to use, identify if the region being revolved creates a solid with a hole (washer) or a solid without a hole (disk). 5. If the region is bounded by one curve and the axis of revolution, use the disk method. 6. If the region is bounded by two curves and the axis of revolution, use the washer method. 7. In summary, use the disk method for solids without holes and the washer method for solids with holes.