Who among the following first prepared a stable compound of a noble gas?

$Xe_{(g)} + 3F_{2(g)} \xrightarrow{573 \ K, 60-70 \ bar} XeF_{6(s)}$ ($1:20$ molar ratio).
$XeF_6 + H_2O \rightarrow XeOF_4 + 2HF$ $(Y)$
$XeF_6 + 3H_2O \rightarrow XeO_3 + 6HF$ $(Z)$
The correct statements regarding $Y$ and $Z$ are:
$I$. $Y$ has square pyramidal geometry
$II$. $Y$ has linear geometry
$III$. $Z$ has $3 \sigma, 3 \pi$ bonds and $1$ lone pair of electrons on the central atom
$IV$. $Z$ has tetrahedral geometry

What is the total number of lone pairs of electrons on the central atom in $XeOF_4$?

Xenon hexafluoride on partial hydrolysis produces compounds $X$ and $Y$. Compounds $X$ and $Y$ and the oxidation state of $Xe$ are respectively

Why does the following reaction occur?
$XeO_{6(aq)}^{4-} + 2F_{(aq)}^{-} + 6H_{(aq)}^{+} \to XeO_{3(g)} + F_{2(g)} + 3H_2O_{(l)}$
What conclusion about the compound $Na_4XeO_6$ (of which $XeO_6^{4-}$ is a part) can be drawn from the reaction?

The noble gas which forms the maximum number of compounds is