With the principle quantum number being 2, the maximum number that can share this is 8. You can use the general formula 2n^2 to calculate this number (n=quantum level), or you can use the concept of quantum numbers (n, l, m, s) to justify this answer.
The answer for the first one is the second option.
The answer for the second one is the last option.
Hope this helped and have a nice day : )
I believe there are 3 significant figures B.
