Identify the product 'B' in the following reaction
$\text{Isopropyl cyanide} \xrightarrow{\large{\text{SnCl}_2, \text{HCl}}} \text{A} \xrightarrow{\large{\text{H}_3\text{O}^+}} \text{B} + \text{NH}_4\text{Cl}$

Benzonitrile on reaction with a reagent in dry ether followed by hydrolysis forms benzophenone along with ammonia and hydroxymagnesium bromide. Identify the reagent used in above transformation.

Identify the product 'B' in the following reaction
$\text{Toluene} \xrightarrow{\large{\text{Chromyl chloride} / \text{CS}_2}} A \xrightarrow{\large{\text{H}_3\text{O}^+}} B$

Identify the product 'Y' in the following reaction $\text{Benzonitrile} \xrightarrow{\large{\text{C}_6\text{H}_5\text{MgBr} / \text{dry ether}}} X \xrightarrow{\large{\text{H}_3\text{O}^+}} Y + \text{MgBr(OH)} + \text{NH}_3$