The slant height of the cone
[tex]\text{slant height = 22.4mi}[/tex]Radius of the base of cone
[tex]\text{ radius = 10 mi}[/tex]The surface area of cone is:
[tex]\text{ Surface are of cone = }\Pi radius\text{ }\times slant\text{ height+}\Pi radius^2[/tex]Substitute the value and simplify
[tex]\begin{gathered} \text{ Surface area of cone = }\frac{22}{7}\times10\times22.4+\frac{22}{7}\times10\times10 \\ \text{Surface area of cone = 1017.9mi}^2 \end{gathered}[/tex]Answer: D) 1017.9 mi^2
