The curves are ,  and about .

Method of washer:

The volume of the solid  is , where  is the cross sectional area of the solid .

Graph:

From the graph, intersection points are   and .

Integral limits are  and .

Outer radius  wlii be distance from the line  to .

.

Inner radius wlii be distance from the line   to  .

.

.

Volume of the solid is,

.

Volume of the solid is .

Volume of the solid is .