In which of the following species,the ratio of $s$-electrons to $p$-electrons is the same?

The number of correct statements from the following:
$A.$ For $1s$ orbital,the probability density is maximum at the nucleus.
$B.$ For $2s$ orbital,the probability density first increases to maximum and then decreases sharply to zero.
$C.$ Boundary surface diagrams of the orbitals enclose a region of $100\%$ probability of finding the electron.
$D.$ $p$ and $d$-orbitals have $1$ and $2$ angular nodes respectively.
$E.$ Probability density of $p$-orbital is zero at the nucleus.

The orbital angular momentum of an electron in an $s$ orbital is:

How is the angular node determined? State the number of angular nodes for $s, p, d,$ and $f$ orbitals.

$Ge$ $(Z=32)$ in its ground state electronic configuration has $x$ completely filled orbitals with $m_{l}=0$. The value of $x$ is ..... .

The maximum number of sub-levels, orbitals and electrons in $N$ shell of an atom are respectively