The total number of structural isomers possible for the molecular formula ${\mathrm{C}}_3{\mathrm{H}}_9\mathrm{N}$ is______.

In the reaction, the product $\left(\mathrm{C}\right)$ is ${\mathrm{C}}_6{\mathrm{H}}_5{\mathrm{NH}}_2\underset{0-5°\mathrm{C}}{\overset{{\mathrm{NaNO}}_2+\mathrm{HCl}}{\to }}\left(\mathrm{A}\right)\underset{\mathrm{KCN}}{\overset{\mathrm{CuCN}}{\to }}\left(\mathrm{B}\right)\stackrel{{\mathrm{H}}^{+}/{\mathrm{H}}_2\mathrm{O}}{⟶}\left(\mathrm{C}\right)$

Reaction of aniline with acetic anhydride in presence of pyridine yields acetic acid and product $\text{'}\mathrm{X}\text{'}$.

What is the total number of groups from the following, present in the compound $\text{'}\mathrm{X}\text{'}$?

Acetylation of aniline with acetic anhydride in presence of pyridine yields acetic acid and product $\text{'}\mathrm{X}\text{'}$.

How many of the below given groups present in the compound $\text{'}\mathrm{X}\text{'}$?

How many of the following will give positive carbylamine test?

Amongst the following, identify the number of compounds that would produce a nauseating smell/odour when treated with a hot mixture of chloroform and ethanolic potassium hydroxide.

${\mathrm{PhCONH}}_2, \mathrm{PhOH}, {\mathrm{PhNH}}_2, (\mathrm{Me}{)}_2{\mathrm{CHNH}}_2$

${\mathrm{PhNHCH}}_3, {\mathrm{PhCH}}_2{\mathrm{NH}}_2, \mathrm{PhN}(\mathrm{Me}{)}_2, (\mathrm{Et}{)}_3\mathrm{N} (\mathrm{Ph}{)}_3\mathrm{N}$