Heating the acyl azide in dry toluene under reflux for $3$ hours gives a $90\%$ yield for a heterocyclic product. Identify the product $(A)$.

Consider the following reaction sequence:
$p$-Nitrotoluene $\xrightarrow{P} Q$ $\xrightarrow{R} S$ $\xrightarrow{H_2O} T$
$S \xrightarrow{U} \text{Benzoic acid}$
Identify the correct statements from the following:
$(A) P = H_2/Pd, \text{ethanol}; R = NaNO_2/HCl; U = 1. H_3PO_2, 2. KMnO_4-KOH, \text{heat}$
$(B) P = Sn/HCl; R = HNO_2; S = p-\text{toluenediazonium chloride}$
$(C) S = p-\text{toluenediazonium chloride}; T = p-\text{cresol}; U = 1. CH_3CH_2OH, 2. KMnO_4-KOH, \text{heat}$
$(D) Q = p-\text{nitrobenzoic acid}; R = H_2/Pd, \text{ethanol}; T = p-\text{cresol}$
Which of the following combinations is correct?

Match the following:

List-$I$ (Amine)	List-$II$ ($pK_b$ value)
$A$. $N,N$-Dimethylaniline	$I$. $9.30$
$B$. Aniline	$II$. $8.92$
$C$. $N$-Ethylethanamine	$III$. $9.38$
$D$. $N$-Methylaniline	$IV$. $3.00$

The correct answer is

Match List-$I$ with List-$II$ and select the correct answer.

List-$I$	List-$II$
$1.$ Aniline	$a.$ Used in the preparation of azo dyes
$2.$ Nitrobenzene	$b.$ Sulpha drug
$3.$ Sulphanilamide	$c.$ Solvent in Friedel-Crafts reaction
$4.$ Trinitrotoluene	$d.$ Used as an explosive

How will you convert:
$(i)$ Benzene into aniline
$(ii)$ Benzene into $N,N$-dimethylaniline
$(iii)$ $Cl-(CH_2)_4-Cl$ into hexane-$1,6$-diamine?

Aniline on treatment with $NaNO_2 / HCl$ at about $0^\circ C$ gives a compound $A$, which on further treatment with $CuCN / KCN$ gives a compound $B$, which when reacts with $H_2 / Ni$ gives a compound $C$. The compound $C$ on reaction with $HNO_2$ gives a compound $D$. The structure of $D$ is: