Which among the following elements has the highest first ionization enthalpy?

In the $2^{nd}$ period,which element has the highest value of the sum of the $1^{st}$ and $2^{nd}$ ionization energy $(I.E.)$?

The correct order of the first ionization enthalpies of the following elements is:

Which of the following statements is correct regarding the first $(I)$ and second $(II)$ ionization enthalpies of sodium $(Na)$ and magnesium $(Mg)$?

$B$ has a smaller first ionization enthalpy than $Be$. Consider the following statements:
$(I)$ It is easier to remove a $2p$ electron than a $2s$ electron.
$(II)$ The $2p$ electron of $B$ is more shielded from the nucleus by the inner core of electrons than the $2s$ electrons of $Be$.
$(III)$ The $2s$ electron has more penetration power than the $2p$ electron.
$(IV)$ The atomic radius of $B$ is more than $Be$.
(Atomic number: $B=5, Be=4$)
The correct statements are:

An atom with high electronegativity has