Which of the following fluorides of Xenon does not exist?

Identify the use of argon from the following.

Match the compounds of $Xe$ in Column-$I$ with the molecular structure in Column-$II$.

Column-$I$	Column-$II$
$(a)$ $XeF_2$	$(i)$ Square planar
$(b)$ $XeF_4$	$(ii)$ Linear
$(c)$ $XeO_3$	$(iii)$ Square pyramidal
$(d)$ $XeOF_4$	$(iv)$ Pyramidal

Assertion : Inert gases are monoatomic.
Reason : Inert gases have stable configuration.

Noble gases are a group of elements that exhibit which of the following?

$A$ gas $X$ is used in filling balloons for meteorological observations. It is also used in gas-cooled nuclear reactors. Here,the gas $X$ is