At what temperature is white phosphorus heated to obtain red phosphorus (in $K$)?

The following are some statements related to $VA$ group hydrides:
$I$. Reducing property increases from $NH_3$ to $BiH_3$.
$II$. Tendency to donate lone pair decreases from $NH_3$ to $BiH_3$.
$III$. Thermal stability of hydrides decreases from $NH_3$ to $BiH_3$.
$IV$. Bond angle of hydrides decreases from $NH_3$ to $BiH_3$.
The correct statements are:

Which one of the following properties is $not$ shown by $NO$?

Identify the reaction which does not liberate $N_2$.

Though nitrogen exhibits $+5$ oxidation state,it does not form pentahalide. Give reason.

An inorganic salt $(A)$ is decomposed at about $523 \ K$ to give products $(B)$ and $(C).$ Compound $(C)$ is a liquid at room temperature and is neutral to litmus paper,while oxide $(B)$ on burning with white phosphorus,gives a dehydrating agent $(D).$ Compounds $(A)$,$(B)$,$(C)$ and $(D)$ will be identified as: