The reaction of aryl halide with sodium metal in dry ether to give biphenyl is known as

Oxidation of toluene with dilute $HNO_3$ gives:

Select the reaction giving the correct major product.

Which of the following reasons support that aryl halides are less reactive than alkyl halides towards nucleophilic substitution reactions?
$a)$ The formation of more stable arenium ion
$b)$ Partial double bond character of $C-X$ bond
$c)$ Longer $C-X$ bond
$d)$ $sp^2$ carbon bonded to $X$ is more electronegative

Which of the following has the highest normal boiling point?

Reaction of aqueous sodium hydroxide on $(i)$ ethyl bromide and $(ii)$ chlorobenzene gives