The equations are
,
,
and
.
(a) Find the volume about the
-axis:
The volume of the solid is
.
Substitute
,
and
.





.
The equations are
,
,
and
.
(b) Find the volume about the
-axis:
Shell method:
\Vertical axis of revolution.
\The volume of the solid is
.
The distance from the center of the rectangle to the axis of revolution is
.
The height of the rectangle is
.
Substitute
,
and
and
in
.




.
The equations are
,
,
and
.
(c) Find the volume about the
:
Shell method:
\The volume of the solid is
.
The distance from the center of the rectangle to the axis of revolution is
.
The height of the rectangle is
.
Substitute
,
and
and
in
.






.
The volume of the solid about the
-axis is
.
The volume of the solid about
-axis is
.
The volume of the solid about
is
.
The volumes of the resulting solids from least to greatest is
.
Therefore,
.
The volumes of the resulting solids from least to greatest is
.