Trigonal bipyramidal geometry is shown by

Which of the following is the correct order of increasing number of lone pair of electrons on the central atom?

The tetra-atomic molecules/ions with different shapes are

$S +$ Conc. $H_2SO_4 \longrightarrow X + Y$
Here $X$ is a gas and $Y$ is a liquid and both are triatomic molecules. The number of electron lone pairs present on the central atoms of $X$ and $Y$ are respectively.

In the structure of $SF_{4}$,the lone pair of electrons on $S$ is in ....

The shape of the $BF_3$ molecule is: