How many orbitals are present in a $g$ subshell?

Consider the following schematic plots of radial orbital wavefunction $(\psi)$ against distance $(r)$ from the nucleus. The figure representing an orbital with two radial nodes is

The electrons identified by quantum numbers $n$ and $l$ :
$A. n=4, l=1$ $B. n=4, l=0$
$C. n=3, l=2$ $D. n=3, l=1$
can be placed in order of increasing energy as :

What is the spin magnetic moment of an electron,excluding its orbital angular momentum?

What is the maximum number of electrons with the same spin that can be accommodated in a shell with principal quantum number $n$?

The quantum number which explains the line spectra observed as doublets in the case of hydrogen and alkali metals, and doublets and triplets in the case of alkaline earth metals is: