Which of the following statements is correct?

The correct formula used to determine the formal charge $(Q_{f})$ on an atom in the given Lewis structure of a molecule or ion is ($V=$ number of valence electrons in free atom,$U=$ number of unshared electrons on the atom,$B=$ number of bonds around the atom)

Identify the pair that is not isostructural.

The formal charges of $N_{(1)}$,$N_{(2)}$ and $O$ atoms in the structure shown below are respectively:
$:N_{(1)}=N_{(2)}=\ddot{O}:$

In which of the following pairs is the product of the Lewis acid and Lewis base reaction also a Lewis base?

Given below are statements about some molecules/ions. Identify the $CORRECT$ statements.
$A$. The dipole moment value of $NF_3$ is higher than that of $NH_3$.
$B$. The dipole moment value of $BeH_2$ is zero.
$C$. The bond order of $O_2^{2-}$ and $F_2$ is same.
$D$. The formal charge on the central oxygen atom of ozone is $-1$.
$E$. In $NO_2$, all the three atoms satisfy the octet rule, hence it is very stable.
Choose the correct answer from the options given below: