The radii of two circular faces of a frustum of a cone are 8 cm and 6 cm. If the height of the frustum is 21 cm, find its volume.

3,256 cm²

Volume of frustum = \(\frac{d}{d}\) \(\pi \) (r₁² + r₂² + r₁r₂) × h

= \(\frac{1}{3}\) \(\pi \) (8² + 6² + 8 × 6) × 21

= \(\frac{1}{3}\) \(\pi \) (64 + 36 + 48) × 21

= \(\frac{1}{3}\) × \(\frac{22}{7}\) × 148 × 21 = 3,256 cm³