Surface area of a sphere is 4πr². Volume is a different formula. Radius 3 gives 36π. Surface area as a set is in surface area.
Wrap, do not fill
If the question is paint or coating, you want 4πr². If it is how much the ball holds, that is volume, in volume of a sphere. A cone has its own wrapping formula, in surface area of a cone.
The short list is in ACT Math formulas.
The bottom line
Sphere surface: 4πr². Halve the diameter first.
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