What is the major product of the following reaction?
$CH_2=CH-CH_2-CH(Br)-CH_3 + KOH \xrightarrow[\text{heat}]{\text{alcohol}} \dots$

Identify the major product $Y$ in the given reaction sequence.

Ethanolic $KOH$ gives

The correct reactivity order for $S_N2$ reaction is:
$(i)$ $CH_3COCH_2Cl$
(ii) $CH_2=CH-CH_2Cl$
(iii) $CH_3CH_2CH_2Cl$

Consider the $S_N1$ solvolysis of the following halides in aqueous formic acid:
$(I)$ $CH_3-CH(CH_3)-CH(Br)-CH_3$
$(II)$ $CH_3-C(CH_3)(Br)-CH_3$
$(III)$ $C_6H_5-CH(Br)-C_6H_5$
$(IV)$ $C_6H_5-CH(Br)-CH_3$
Which one of the following is the correct sequence of the halides given above in the decreasing order of their reactivity?

What is the product formed by the reaction of $HBr$ with $CH_2=CH-OCH_3$ under anhydrous conditions at room temperature?