Identify the product '$B$' in the following reaction: $CH_3 - I \xrightarrow{KCN} A \xrightarrow{Na/C_2H_5OH} B$

When ethanol is mixed with ammonia and passed over alumina,the compound formed is:

Indicate which nitrogen compound amongst the following would undergo Hofmann's reaction (i.e.,reaction with $Br_2$ and strong $KOH$) to furnish the primary amine $(R-NH_2)$.

Identify the end product $(B)$ containing nitrogen in the following reaction sequence:

Predict the major product $P$ in the following sequence of reactions$-$
$(i)$ $HBr$,benzoyl peroxide
(ii) $KCN$
(iii) $Na(Hg)/C_2H_5OH$
[Image: $1-$methylcyclopentene reacting with the above reagents to form $P$]

Why cannot aromatic primary amines be prepared by Gabriel phthalimide synthesis?