Which of the following is a neutral oxide?

On heating copper nitrate strongly,$.......$ is finally obtained.

Assertion : $PbI_4$ is a stable compound.
Reason : Iodide stabilizes higher oxidation state.

The element $X$ which forms a stable product of the type $XCl_4$ is $....$

What is the value of $\angle S-S-S$ in the puckered $S_8$ ring of rhombic sulfur (in $^{\circ}$)?

In the following reaction,assign the state for the underlined atom for the product of complete hydrolysis at $R.T.$:
$\underline{N}O + H_2O \longrightarrow$ No reaction