1. Volume between x^2+y^2=9 and y=(4-x^2)^(½) Rotated about the x-axis

2. In an xy-plane a volume is represented by perpendicular cirles
Cross seciton centered at y=9
Use y=(x-1)^2 as an edge on [0,2]
Use y=(x+1)^2 as an edge on [-1,0]

3. Cross sections are perpendicular to page
Only cross sections with constant y should be used and x values less than 3
All values less than or equal to |ln(x)|
Cross sections are triangles 30 deg into the positive z axis

4. Hexagon Cross section where one point is on the line and the distance furthest point to point accross the hexagon is 6
The line that the points follow is on x^2+y^2=16
This volume only exists x=[2(2)^(½),4] in the first quadrant