8. What is the maximum number of parts into which the surface of a sphere (sphere) can be divided by 3, 4, and, generally, $n$ circles?
8. One circle divides the sphere into 2 parts, two circles into 4 parts if they are not parallel and intersect, three circles can divide the sphere into a maximum of 8 parts, 4 circles can divide it into a maximum of 14 parts, and $n$ circles can divide the sphere into a maximum of $n^{2}-n+2$ parts.