Chlorination of $Benzene$ in the presence of sunlight gives

Which position will be attacked most rapidly by the nitronium ion $(NO_2)^+$ when the compound undergoes nitration with $HNO_3 / H_2SO_4$?

Which of the following is non-aromatic?

The heat of hydrogenation of one double bond in cyclohexene is $28.6 \, kcal \, mol^{-1}$ and the heat of hydrogenation of benzene to cyclohexane is $50 \, kcal \, mol^{-1}$. The resonance stabilization energy of benzene is ...... $kcal \, mol^{-1}$.

Considering the reaction shown below,identify the major product:

Why does benzene undergo electrophilic substitution reactions easily and nucleophilic substitutions with difficulty?