What is the product obtained when the product of alkaline hydrolysis of $C_2H_5 - N = C = O$ is reacted with $t$-butyl magnesium bromide?

$STATEMENT-1$: Aniline on reaction with $NaNO_2 / HCl$ at $0^{\circ} C$ followed by coupling with $\beta$-naphthol gives a dark blue coloured precipitate.
$STATEMENT-2$: The colour of the compound formed in the reaction of aniline with $NaNO_2 / HCl$ at $0^{\circ} C$ followed by coupling with $\beta$-naphthol is due to the extended conjugation.

$p$-Toluidine reacts with benzene diazonium chloride to form a compound,which on boiling with $aq. H_2SO_4$ gives ........ products.

The structure of the product will be:

Give a plausible explanation for each of the following:
$(i)$ Why are amines less acidic than alcohols of comparable molecular masses?
$(ii)$ Why do primary amines have higher boiling points than tertiary amines?
$(iii)$ Why are aliphatic amines stronger bases than aromatic amines?

$A$ nitrogen-containing organic compound gave an oily liquid on heating with bromine and potassium hydroxide solution. On shaking the product with acetic anhydride,an antipyretic drug was obtained. The reactions indicate that the starting compound is