Given: Diameter of the base of a cylinder is 28 cm.

Its height is 20 cm.

Volume of the Cylinder is given by: 2πr(r + h). (here r and h are radius and diameter respectively)

Let S be the Surface area of the cylinder.

∴ V = 2πr(r + h)

⇒ S = 2 × π × () × [() + 20] (∵ 28 is the diameter and is the radius)

⇒ V = 2 × π × 14 × (14 + 20) = 2 × π × 14 × 24

⇒ V = 2992 cm²

∴ The Surface area of the cylinder is 2992 cm²