Consider the reaction: $CH_3-CH_2-CH(F)-CH_3 \xrightarrow{CH_3O^{-}} X$. The alkene formed in major amount is:

The products $A$ and $B$ in the following reactions,respectively,are:
$A \xleftarrow{AgNO_2} CH_3-CH_2-CH_2-Br \xrightarrow{AgCN} B$

What are $X$ and $Y$ respectively in the following reactions?

Among the following chlorides, the compounds which will be hydrolysed most easily and most slowly in aqueous $NaOH$ solution are respectively:
$1$. Methoxymethyl chloride $(CH_3OCH_2Cl)$
$2$. Benzyl chloride $(C_6H_5CH_2Cl)$
$3$. Neopentyl chloride $((CH_3)_3CCH_2Cl)$
$4$. Propyl chloride $(CH_3CH_2CH_2Cl)$

The major product of the following reaction is:

Elimination of bromine from $2-$bromobutane results in the formation of