What is the maximum number of electrons that can be accommodated in a shell with principal quantum number $n = 4$?

What is the number of orbitals in the $2p$ and $3p$ subshells? Where are they located?

The number of $d$ electrons in $Fe$ is equal to which of the following?
$i$. Total number of '$s$' electrons of $Mg$
$ii$. Total number of '$p$' electrons of $Cl$
$iii$. Total number of '$p$' electrons of $Ne$
The correct option is

The maximum number of electrons that can be filled in the shell with the principal quantum number $n=3$ is

The number of angular nodes and radial nodes in $3s$ orbital are

If $n + l = 6$,then the total possible number of subshells would be