The $E_2$ product of the following reaction will be?

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 $(CH_3CH_2CH_2Cl)$

Which one of the following is chiral?

The products $A$ and $B$ formed in the above reactions are

Which of the following compounds has the fastest $S_N2$ reaction rate?

An 'Assertion' $(A)$ and a 'Reason' $(R)$ are given below. Choose the correct answer from the following options.
Assertion $(A)$: Vinyl halides do not undergo nucleophilic substitution easily.
Reason $(R)$: Even though the intermediate carbocation is stabilized by loosely held $p-$ electrons,the cleavage is difficult because of strong bonding.