Will give brainliest. 50 points.. find the surface area of the cone in terms of pi .

so, the diameter of the cone is 12 cm, therefore its radius is 6 cm, keeping in mind its slant height is 18 cm.

The base area is given by

... A = π·r²

For a radius of 6 cm, this is

... A = π·(6 cm)² = 36π cm²

The lateral area is given by

... A = (1/2)C·s = (π/2)d·s

where C is the circumference of the base, d is the base diameter, and s is the slant height.

For a base diameter of 12 cm, this is

... A = (π/2)·(12 cm)·(18 cm) = 108π cm²

Then the total surface area of the cone is

... surface area = base area + lateral area

... surface area = (36π cm²) + (108π cm²)

... surface area = 144 cm²