the position of an electron can be explained in 4 quantum numbers
the principal quantum number - n - tells the size of the energy shell
and azimuthal quantum number - l - gives the shape of the orbital or the number of subenergy shells
values of l are from 0 to n-1
since n = 4
values for l are 0,1,2 and 3
theres a total of 4 energy sublevels - s,p, d and f