Which of the following molecules is not aromatic?

Give the reaction for the formation of $m$-dinitrobenzene from benzene.

Total number of aromatic compounds among the following compounds is:

In the sulphonation,acetylation and formylation of benzene,the group of effective electrophiles would be:

Product $(A)$ is

In which of the following reactions,$t$-butyl benzene is formed?
$1.$ Benzene $+ t$-butyl chloride $\xrightarrow{AlCl_3}$
$2.$ Benzene $+ (CH_3)_2C=CH_2 \xrightarrow{BF_3/HF}$
$3.$ Benzene $+ t$-butyl alcohol $\xrightarrow{H_2SO_4}$
$4.$ Benzene $+$ butanoyl chloride $\xrightarrow{AlCl_3}$ $\xrightarrow{Zn/Hg, HCl}$