# Volume of a torus

## Calculates the volume and surface area of a torus given the inner and outer radii.

 b≧a

volume V
surface area S

 $\normal Torus\\(1)\ volume:\hspace{50} V={\large\frac{1}{4}}\pi^2(a+b)(b-a)^2\\(2)\ surface\ area:\hspace{10} S=\pi^2(b^2-a^2)\\$

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