The product $(A)$ is:

Which set of products will be obtained in the following reactions?
$RCN \xrightarrow{\text{reduction}} (a)$
$RCN \xrightarrow[(ii) H_2O]{(i) CH_3MgBr} (b)$
$RNC \xrightarrow{\text{hydrolysis}} (c)$
$RNH_2 \xrightarrow{HNO_2} (d)$

Product $D$ is:-

How many isomeric forms of $C_7H_9N$ contain a benzene ring?

$A$ hydrocarbon $'A'$ $(C_4H_8)$ on reaction with $HCl$ gives a compound $'B'$ $(C_4H_9Cl)$,which on reaction with $1 \ mol$ of $NH_3$ gives compound $'C'$ $(C_4H_{11}N)$. On reacting with $NaNO_2$ and $HCl$ followed by treatment with water,compound $'C'$ yields an optically active alcohol,$'D'$. Ozonolysis of $'A'$ gives $2 \ mols$ of acetaldehyde. Identify compounds $'A'$ to $'D'$. Explain the reactions involved.

$(i)$ Write structures of different isomeric amines corresponding to the molecular formula,$C_{4}H_{11}N$. $(ii)$ Write $IUPAC$ names of all the isomers. $(iii)$ What type of isomerism is exhibited by different pairs of amines?