Who discovered the first noble gas?

What inspired $N. \ Bartlett$ to carry out the reaction between $Xe$ and $PtF_6$?

In reaction $(1)$, $XeF_6$ undergoes complete hydrolysis to form $HF$ and $X$. In reaction $(2)$, $XeF_6$ undergoes partial hydrolysis to form $HF$, $Y$, and $Z$. The products $X, Y, Z$ respectively, are

Which mixture is used for respiration by deep sea divers?

What is the atomic number $(Z)$ of the noble gas that reacts with fluorine?

The hybridisation and structure of $XeF_6$ is :