shell electrons

[cricket]

I can't make sense out of this question.

Krypton has 36 electrons. How many electrons are in the n = 5 shell?

It's in the 4th period so why are they asking for the 5th shell?
The answer is listed as 4 electrons but how?

2,8,18,8 = 36
so Kr has 8 in the last shell (n=4)

[himanshu121]

4e too is not so formidable coz Kr is in Noble Gas Group so it will have fully filled orbitals.