$CH_{3}CH_{2}Br$ $\xrightarrow[\Delta]{aq. KOH} A$ $\xrightarrow[\Delta]{KMnO_{4} / H^{+}} B$ $\xrightarrow[\Delta]{NH_{3}} C$ $\xrightarrow[alkali]{Br_{2}} D$. '$D$' is

Nitrobenzene on treatment with zinc dust and aqueous ammonium chloride gives

Predict the reagents or products $(1)$ to $(5)$ in the following reaction sequence:
$p-Nitrotoluene$ $\xrightarrow{(1)} p-Toluidine$ $\xrightarrow{(CH_3CO)_2O/\text{Pyridine}} p-Acetotoluidide$ $\xrightarrow{HNO_3/H_2SO_4} (2)$ $\xrightarrow{(3)} (4)$ $\xrightarrow{(5)} 3-Nitrotoluene$

The major product formed by the reaction of benzylamine with nitrous acid is

Compound $A$ is converted to $B$ on reaction with $CHCl_3$ and $KOH$. The compound $B$ is toxic and can be decomposed by $C$. $A, B$ and $C$ respectively are:

What is the correct order of basicity for the following compounds?
$1$. $C_6H_5NH_2$ (Aniline)
$2$. $CH_3CH_2NH_2$ (Ethylamine)
$3$. $(CH_3)_2NH$ (Dimethylamine)
$4$. $CH_3CONH_2$ (Acetamide)