The product $(Z)$ of the following reaction is

Aromatic molecules do not possess which of the following?

The major product of the following reaction is:

The major product$(s)$ of the following reaction is (are):

Which of the following statements are correct?
$I$. In nitrating mixture,nitric acid participates as an acid.
$II$. $\sigma$-complex is the intermediate substance in electrophilic substitution of benzene.
$III$. Benzene on Friedel-Crafts alkylation with $n$-propyl chloride gives isopropyl benzene.

Which of the following benzene rings is most reactive towards an electrophile $(E^{\oplus})$?