Which one is a polar molecule?

Among the following compounds,the one which shows the highest dipole moment is

Which among the following molecules is non-polar?

Arrange the following in order of increasing dipole moment: $H_2O, H_2S, BF_3$.

The percentage ionic character of the $HBr$ molecule, if the dipole moment is $0.63 \ D$ and $HBr$ bond length is $187.5 \ pm$, is:

The observed dipole moment of $HCl$ is $1.303 \ D$. This indicates that $HCl$ has $17 \%$ ionic and $83 \%$ covalent character. The bond length of $HCl$ is $1.26 \ \mathring{A}$ and the charges on $H$ and $Cl$ ions are $+e$ and $-e$. Calculate the theoretical dipole moment in $D$.