$TNT$ has the structure

Which of the following structures are aromatic in nature?

Three fused benzene rings are found in

Benzene reacts with chlorine to form benzene hexachloride in the presence of:

The reaction shown below proceeds through which mechanism?

Nitrobenzene can be prepared from benzene by using a mixture of conc. $HNO_3$ and conc. $H_2SO_4$. In the nitrating mixture,$HNO_3$ acts as a