A tent is in the form of a right circular cylinder surmounted by a cone. The diameter of the cylinder is 24 m. The height of the cylindrical portion is 11 m while the vertex of the cone is 16 m above the ground. The area of the canvas required for the tent is :

Answer: Option C

Radius, r = 12 m
Height of conical part, h = (16 - 11) m = 5 m
Slant height of conical part,
$$\begin{array}{rl}& l=\sqrt{r^2+h^2}\\ & =\sqrt{{\left(12\right)}^2+{\left(5\right)}^2}\\ & =\sqrt{169}\\ & =13m\end{array}$$
Height of cylindrical part, H = 11 m
Area of canvas required :
= Curved surface area of cylinder + Curved surface area of cone
$$\begin{array}{rl}& =2\pi rH+\pi rl\\ & =\left[\frac{22}{7}\left(2\times 12\times 11+12\times 13\right)\right]{\text{m}}^2\\ & =\left[\frac{22}{7}\left(264+156\right)\right]{\text{m}}^2\\ & =\left(\frac{22}{7}\times 420\right){\text{m}}^2\\ & =1320{\text{m}}^2\end{array}$$