This applet is a visualization of the solid of revolution generated by revolving the region bounded by , the x-axis, and x = 4 about the y-axis. There are options to display the solid of revolution and/or an approximating washer and/or an approximating shell.

Write an expression that gives the volume of an approximating washer.

Write an integral that represents the volume of the solid of revolution using the method of washers.

Write an expression that gives the volume of an approximating shell.

Write an integral that represents the volume of the solid of revolution using the method of shells.