Identify major product $$\mathrm{A}$$ in following reaction.

3-Bromo-2-methylpentane $$\mathrm{\mathrel{\mathop{\kern0pt\longrightarrow} \limits_\Delta ^{alc.KOH}}}$$ A

The molecular formula of hexachlorobenzene is

Identify the final product formed on ammonolysis of benzyl chloride followed by the reaction with two moles of $$\mathrm{CH}_3 \mathrm{I}$$.

When tert-butyl bromide is heated with silver fluoride, the major product obtained is: