If $H-X$ bond length is $2 \ \mathring{A}$ and $H-X$ has dipole moment $5.12 \times 10^{-30} \ C \cdot m$,the $\%$ of covalent character of the molecule is ............. $\%$

Match the following molecules in List-$I$ with their respective dipole moments in List-$II$.

List-$I$ (Molecules)	List-$II$ (Dipole moment)
$A$. $HBr$	$I$. $1.04$
$B$. $H_2S$	$II$. $0$
$C$. $NH_3$	$III$. $0.79$
$D$. $CHCl_3$	$IV$. $0.95$
	$V$. $1.47$

Statement $I$: Dipole moment is a vector quantity and by convention it is depicted by a small arrow with tail on the positive centre and head pointing towards the negative centre.
Statement $II$: The crossed arrow of the dipole moment symbolizes the direction of the shift of charges in the molecules.
In the light of the above statements,choose the most appropriate answer from the options given below :-

Which one of the following molecules is polar?

Write the significance and applications of dipole moment.

The dipole moment of $HBr$ is $1.6 \times 10^{-30} \ C \ m$ and interatomic spacing is $1 \ \mathring{A}$. The $\%$ ionic character of $HBr$ is