$1,4-$dimethylbenzene on heating with anhydrous $AlCl_{3}$ and $HCl$ produces

Benzene was discovered by

Given below are two statements:
Statement $I$: Nitration of benzene involves the following step:
$H-O^+(H)-NO_2 \rightleftharpoons H_2O + NO_2^+$
Statement $II$: Use of Lewis base promotes the electrophilic substitution of benzene.
In the light of the above statements,choose the most appropriate answer from the options given below:

The non-aromatic compound among the following is

The bond angle between carbon atoms in a benzene molecule is

How many hydroxy groups are present in hydroxyquinol?