Write the structures of the major products expected from the following reactions:
$(a)$ Mononitration of $3-$methylphenol
$(b)$ Dinitration of $3-$methylphenol
$(c)$ Mononitration of phenyl methanoate.

$p$-Hydroxybenzophenone upon reaction with bromine in carbon tetrachloride gives

Reaction of phenol with which of the following reagents forms picric acid?

Given below are two statements: one is labelled as Assertion $A$ and the other is labelled as Reason $R$:
Assertion $A$: Aryl halides cannot be prepared by the replacement of the hydroxyl group of phenol by a halogen atom.
Reason $R$: Phenols react with halogen acids violently.
In the light of the above statements,choose the most appropriate from the options given below:

The acidity of the following compounds follows the order:
$I$: Phenol
$II$: $p$-Methoxyphenol
$III$: $p$-Nitrophenol
$IV$: $m$-Nitrophenol

In the reaction sequence,phenol reacts with $HNO_2$ to form $X$,which then reacts with phenol in the presence of $H_2SO_4$ to form $Y$. Identify the major products $X$ and $Y$.