What formula do you use?

Answer:
The hole is a cone and it's asking for the surface so am guessing the top of the hole and so for that it would be a circle. And a surface is also the area of something. so:
To find the area of a circle with the radius, square the radius, or multiply it by itself. Then, multiply the squared radius by pi, or 3.14, to get the area. Or A=πr^2
To find the area with the diameter, simply divide the diameter by 2, plug it into the radius formula, and solve as before.
Hope this helps!! If so please mark brainliest and rate/heart to help my account if it did!!