Conversion of chlorobenzene to phenol by aqueous sodium hydroxide requires high temperature of about $623 \mathrm{K}$ and high pressure. Explain.

  

Identify the product $\mathrm{A}$ of following reaction:

The correct order of increasing reactivity of $\mathrm{C}-\mathrm{X}$ bond towards nucleophile in the following compounds is,

${\mathrm{CH}}_3-\mathrm{CH}={\mathrm{CH}}_2\underset{\mathrm{peroxide}}{\overset{ \mathrm{HI} }{\to }}$

The major product of the above reaction is,

Which of the following is likely to undergo racemisation during alkaline hydrolysis?