Answer: OPTION A
Step-by-step explanation:
The formula that is used to calculate the surface area of a cone is:
[tex]SA=\pi rl+\pi r^2[/tex]
Where "r" is the radius and "l" is the slant height.
You can identify in the figure that:
[tex]l=12units\\r=3units[/tex]
Then, you need to substitute these values into the formula [tex]SA=\pi rl+\pi r^2[/tex].
Therefore, the surface area of this right cone is:
[tex]SA=\pi (3units)(12units)+\pi (3units)^2[/tex]
[tex]SA=45\pi\ units^2[/tex]
