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.

Propyne on reaction with water in presence of $40\%$ sulphuric acid and $1\%$ mercuric sulphate forms

Identify final products in the following sequence of reactions
$\text{RCOOH} + \text{R'OH} \xrightarrow{\large{\text{H}^+}} \text{intermediate} \xrightarrow{\large{\text{Ni}, \Delta}}^{\large{\text{H}_2}} \text{Products}$