Which of the following is among the major products of the reaction of $(E)-3$-methylpent$-2$-ene with $BH_3$ in $THF$ followed by the addition of $H_2O_2/HO^{-}$?

In which of the following reactions $1,3$-butadiene will be obtained as a major product?

What are $B$ and $C$ respectively in the following set of reactions?
$C \xleftarrow[\Delta]{Zn} 1,2-\text{dibromopropane}$ $\xrightarrow[\text {(ii) } NaNH_2]{\text {(i) alc. } KOH} A$ $\xrightarrow[\text { Catalyst }]{\text { Lindlar }} B$

Which of the following reactions do not represent the major product of given Birch reductions?

Match the following reactions with their nature and choose the correct code.

Reaction	Nature of reaction
$A. RBr \xrightarrow{Na}$	$1. \text{Partial reduction}$
$B. RCOO^-Na^+ \xrightarrow{NaOH/CaO, \Delta}$	$2. \text{Electrophilic addition}$
$C. R-C \equiv C-R' \xrightarrow{\text{Lindlar's catalyst } (H_2)}$	$3. \text{Wurtz reaction}$
$D. H_2C=CH_2 \xrightarrow{Br_2/CCl_4}$	$4. \text{Decarboxylation}$
	$5. \text{Decarboxylative dimerisation}$

Octane number can be changed by