Find the volume for the region enclosed by y=x^2/2 and y=2 when:

1) The region is revolved around the y-axis
2 The region is revolved around the x-axis
3) The region is revolved around the line y=-1
4) The region is revolved around the line x=4

What do you need help on exactly? Have you tried doing the work?

I just need help on starting the problem

Your book has examples for stuff like this, I'm sure.

If you're totally unsure how to even get started, remember that for almost any problem that asks you to find the area/volume of a region of a curve it would be wise to sketch the graph, and then find the limits of integration (what two x values on an interval you will be integrating from) unless they are already given to you.

http://tutorial.math.lamar.edu/Classes/CalcI/VolumeWithCylinder.aspx

Is a great guide for these. The first two should be relatively simple after you determine where the functions intersect(Hint: substitute either x or y in one of the equations. There are two points of intersection in this problem)