Which of the following oil is obtained from benzene after fractional distillation of coal tar?

Number of $\pi$ electrons present in naphthalene is

Identify the number of aromatic compounds from the following structures:
$(i)$ $1,2,4$-triazole
(ii) $2$-pyrone
(iii) Benzimidazole
(iv) Pyrazole
$(v)$ Cyclooctatetraene dianion
(vi) Pyrrolidinium cation
(vii) Cyclopentadienyl cation

Which of the following is the strongest $o,p$-directing group?

The total number of compounds from the list below that,when treated with hot $KMnO_4$,yield benzoic acid is:

Carbon-Carbon bond length in benzene is $.....$ $\mathring{A}$