Identify $A$ in the following reaction.

How will you carry out the following conversion: $p$-nitroaniline to $3,4,5$-tribromonitrobenzene?

Which of the following arylamines will not form a diazonium salt on reaction with sodium nitrite in hydrochloric acid?

Which of the following amines on heating with chloroform generates a foul-smelling product?

Assertion : Acylation of amines gives a monosubstituted product whereas alkylation of amines gives polysubstituted product.
Reason : Acyl group sterically hinders the approach of further acyl groups.

How many amines with molecular formula $C_3H_9N$ can react with benzene sulphonyl chloride?