Identify the product obtained when $2-\text{chloro}-2-\text{methylbutane}$ is reacted with sodium metal in the presence of dry ether.

$ \xrightarrow[Acetone]{NaI} \underset{(Major)}{X} $ $ \xrightarrow[{S_N2}]{aq. KOH} \underset{(Major)}{Y} $
$X$ and $Y$ should be

In a $S_N2$ substitution reaction of the type $R-Br + Cl^- \xrightarrow{DMF} R-Cl + Br^-$,which one of the following has the highest relative rate?

Among the following,the compounds which can undergo an $S_{N}1$ reaction in an aqueous solution are:

Given below are two statements: one is labelled as Assertion $(A)$ and the other is labelled as Reason $(R)$ :
Assertion $(A)$ : $S_N2$ reaction of $C_6H_5CH_2Br$ occurs more readily than the $S_N2$ reaction of $CH_3CH_2Br$.
Reason $(R)$ : The partially bonded unhybridized $p$-orbital that develops in the trigonal bipyramidal transition state is stabilized by conjugation with the phenyl ring.
In the light of the above statements,choose the most appropriate answer from the options given below:

Which compounds give $\beta$-elimination reactions? What are their main products?