Identify correct decreasing order of basic strength of amines from following.

Identify the product ' $B$ ' in the following sequence of reactions.

$$ \text { Ethanenitrile } \xrightarrow{\mathrm{SnCl}_2 . \mathrm{HCl}^{\mathrm{}}} \mathrm{~A} \xrightarrow{\mathrm{H}_3 \mathrm{O}^{+}} \mathrm{B}+\mathrm{NH}_4 \mathrm{Cl} $$

Identify secondary amine from following.

What is the number of moles of hydrogen atoms required to reduce one mole of nitroethane completely using Sn and HCl ?