Ans: C
Let $r\text{ cm}$ and $h\text{ cm}$ be the base radius and the height of the right circular cone respectively. Then we have
Let $r\text{ cm}$ and $h\text{ cm}$ be the base radius and the height of the right circular cone respectively. Then we have
$\begin{array}{rcl}
\dfrac{1}{3} \times \pi \times (r)^2 \times h & = & 36\pi \\
r^2h & = & 108 \text{ cm}^3
\end{array}$
The volume of the circular cylinder
$\begin{array}{cl}
= & \pi \times (\dfrac{r}{2})^2 \times (3h) \\
= & \dfrac{3}{4} \pi r^2 h \\
= & \dfrac{3}{4} \pi (108) \\
= & 81\pi \text{ cm}^3
\end{array}$
