Which product is obtained on treating phenol with concentrated $HNO_3$?

Benzene $+ CH_3CH_2CH_2Cl$ $\xrightarrow{AlCl_3} M$ $\xrightarrow{(i) O_2/\Delta , (ii) H_3O^+} N + \text{phenol}$. Here $M$ and $N$ are

How many $\sigma$ (sigma) and $\pi$ (pi) bonds are present respectively in the final product obtained by the Reimer-Tiemann reaction of phenol?

Out of $o-$nitrophenol and $o-$cresol,which is more acidic?

What amount of bromine will be required to convert $2 \ g$ of phenol into $2, 4, 6-$tribromophenol (in $g$)? $($Given molar mass in $g \ mol^{-1}$ of $C, H, O, Br$ are $12, 1, 16, 80$ respectively$)$

Phenol on treatment with dil. $HNO_3$ gives two products $P$ and $Q$. $P$ is steam volatile but $Q$ is not. $P$ and $Q$ are,respectively: