Noble gases are absorbed by

Among the following molecules:
$(i)$ $XeO_3$
$(ii)$ $XeOF_4$
$(iii)$ $XeF_6$
Those having the same number of lone pairs on $Xe$ are:

Which inert gas has the highest boiling point?

The noble gases have closed-shell electronic configuration and are monoatomic gases under normal conditions. The low boiling points of the lighter noble gases are due to weak dispersion forces between the atoms and the absence of other interatomic interactions.
The direct reaction of xenon with fluorine leads to a series of compounds with oxidation numbers $+2, +4$ and $+6$. $XeF_4$ reacts violently with water to give $XeO_3$. The compounds of xenon exhibit rich stereochemistry and their geometries can be deduced considering the total number of electron pairs in the valence shell.
$1.$ Argon is used in arc welding because of its
$A.$ low reactivity with metal
$B.$ ability to lower the melting point of metal
$C.$ flammability
$D.$ high calorific value
$2.$ The structure of $XeO_3$ is
$A.$ linear
$B.$ planar
$C.$ pyramidal
$D.$ $T$-shaped
$3.$ $XeF_4$ and $XeF_6$ are expected to be
$A.$ oxidizing
$B.$ reducing
$C.$ unreactive
$D.$ strongly basic
Give the answer for questions $1, 2$ and $3$.

Argon is used:

Consider the following transformations:
$I. XeF_6 + NaF \to Na^+[XeF_7]^-$
$II. 2PCl_{5(s)} \to [PCl_4]^+[PCl_6]^-$
$III. [Al(H_2O)_6]^{3+} + H_2O \to [Al(H_2O)_5OH]^{2+} + H_3O^+$
Which of the above transformations are correct?