This may be hard to visualize without a graph, so I apologize in advance, but here is my question:

There is a circle with radius 'b' that is 'a' units away from the y-axis. if the circle is rotated about the y-axis, how do you find the volume of the doughnut that is formed? (assume that b<a)

I would even appreciate a jump start! Anything, really! Thank you in advanced!