The diagram represents a large wooden cone of height 9 cm and base diameter 12 cm. The large cone is made by placing a small cone A of height 3 cm and base diameter 4 cm on top of a frustum B.

$$Volume\; of\; cone=\frac{1}{3}\pi r^{2}h$$ $$Curved\; surface\; area\; of\; cone=\pi rl$$