Chapter 15, Problem 13P

The plane $\frac{x}{a}+\frac{y}{b}+\frac{z}{c}=1a>0,b>0,c>0$cuts the solid ellipsoid $\frac{x^2}{a^2}+\frac{y^2}{b^2}+\frac{z^2}{c^2}\le 1$ into two pieces. Find the volume of the smaller piece.