The surface of cone consists of the lateral surface and the base area. So,
1. the lateral surface is equal to [tex]\pi Rs[/tex], where R is the radius of the base and s is the slant height of the cone;
2. the base area is [tex]\pi R^2[/tex] (since base is a circle with radius R).
Then the surface area is [tex]SA=\pi Rs+\pi R^2[/tex].
You have only to put in correct numbers.
