Nitration of nitrobenzene yields .....

Calculate the sum of $\alpha$-hydrogen atoms in the given structures $(i)$ and $(ii)$:
$(i)$ $1,3$-dimethylbenzene
(ii) $1,3$-diethylbenzene
Sum $= (i) + (ii) = ?$

$C_6H_6 + 3Cl_2 \xrightarrow{UV \ \text{light}} \text{Product}$. In the above reaction,the product is:

Answer the following questions: Which product is obtained when benzene is heated with $CH_3Cl$ in the presence of $AlCl_3$? Why?

Among the given organic compounds,the total number of aromatic compounds is $....$.

Which order is correct for the decreasing reactivity to ring monobromination of the following compounds: $C_6H_5CH_3$ $(I)$,$C_6H_5COOH$ $(II)$,$C_6H_6$ $(III)$,and $C_6H_5NO_2$ $(IV)$?