The products $Q$ and $R$ in the following reactions respectively are:
$H_2 + CH_3-C \equiv CH$ $\xrightarrow{\text{Lindlar's catalyst}} P$ $\xrightarrow[Zn + H_2O]{O_3} Q + R$

Which hydrogen in compound $(E)$ is easily replaceable during bromination reaction in the presence of light?
$CH_3 - CH_2 - CH = CH_2$
$(E)$

Given below are two statements.
Statement $I :$ The presence of weaker $\pi$-bonds makes alkenes less stable than alkanes.
Statement $II :$ The strength of the double bond is greater than that of carbon-carbon single bond.
In the light of the above statements,choose the correct answer from the options given below.

The predominant product formed when $3$-methyl-$2$-pentene reacts with $HOCl$ is:

Consider compounds $A$,$B$ and $C$ with following structural formulae: $A = CH_{3} - CH_{2} - CH_{2} - CH_{2} - CH_{2} - OH$,$B = CH_{2} = CH - CH_{2} - CH_{2} - CH_{3}$,$C = HO - CH_{2} - CH_{2} - CH(OH) - CH_{3}$. For the conversion of $B$ from $A$,reagent $(D)$ required is . . . . . . and structural formula of product $(E)$ obtained when $C$ undergoes same reaction using excess reagent $(D)$ is . . . . . . .

$cis-3-hexene \xrightarrow{(a)} \text{meso } 3,4-hexanediol$
$trans-3-hexene \xrightarrow{(b)} \text{meso } 3,4-hexanediol$
Choose the pair of reagents $(a, b)$ for the above conversions.