The reaction of methyl bromide with aqueous sodium hydroxide involves:

In the reaction of $2$-chlorobutane with aqueous $KOH$,the product $A$ formed is:

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 $(CH_3CH_2CH_2Cl)$

Assertion: $2-$Bromobutane on reaction with sodium ethoxide in ethanol gives $1-$butene as a major product.
Reason: $1-$Butene is more stable than $2-$butene. According to Saytzeff's rule,$2-$butene should be the product which is more branched or substituted compound and hence,more stable than $1-$butene.

Alkyl halide is converted into alkyl isocyanide by reaction with

$A$ haloalkane undergoes $S_{N}2$ or $S_{N}1$ reaction depending on