What is the alkene formed as a major product in the above elimination reaction?

What is the correct order of ${\mathrm{pK}}_{\mathrm{b}}$ of the given amines in benzene?

$\underset{\mathrm{Optically} \mathrm{active}}{\mathrm{X}\left({\mathrm{C}}_5{\mathrm{H}}_{13}\mathrm{N}\right)}\stackrel{{\mathrm{NaNO}}_2/\mathrm{HCl}}{\to }\underset{\left(\mathrm{major}\right)}{\mathrm{Y}\left(3^{\circ } \mathrm{alcohol}\right)}$

Which of the following is incorrect about the above reaction?

Consider the following ions:

The reactivities of these ions in azo-coupling reactions (under similar conditions) will be:

The reaction of a given compound with ${\mathrm{NaNO}}_2$ and $\mathrm{HCl}$ forms $\mathrm{X}$ as the major product. What is true about $\mathrm{X}$?

In the above reactions:
$\left(\mathrm{a}\right)$ $\mathrm{X}$ and $\mathrm{Y}$ are isomers.
$\left(\mathrm{b}\right)$ $\mathrm{X}$ and $\mathrm{Y}$ are $1°$ amines.
$\left(\mathrm{c}\right)$$\mathrm{X}$ and $\mathrm{Y}$ are homologous.
$\left(\mathrm{d}\right)$ $\mathrm{Y}$ is the bromo derivative of $\mathrm{X}$.

The correct statements are: