Answer
The height of the cone is 12 inches.
Work Step by Step
The formula for the volume of a right circular cone is: V = $\frac{1}{3}$ $\times$ $\pi$ $\times$ $r^{2}$ $\times$ h
Substitute 324$\pi$ for V and 9 for r to obtain:
324$\pi$ = $\frac{1}{3}$ $\times$ $\pi$ $\times$ $9^{2}$ $\times$ h
324$\pi$ = $\frac{1}{3}$ $\times$ $\pi$ $\times$ 81 $\times$ h
Multiply both sides by 3
972$\pi$ = $\pi$ $\times$ 81 $\times$ h
Divide both sides by 81$\pi$
h = 12
