The structural formula of $3,4$-benzpyrene is ...... .

The reaction$(s)$ leading to the formation of $1,3,5-$trimethylbenzene is (are):
$(A)$ $3CH_3COCH_3 \xrightarrow{Conc. H_2SO_4, \Delta} 1,3,5-\text{trimethylbenzene}$
$(B)$ $3CH_3C \equiv CH \xrightarrow{\text{heated iron tube}, 873 K} 1,3,5-\text{trimethylbenzene}$
$(C)$ $1,3,5-\text{triacetylbenzene} \xrightarrow{1) Br_2, NaOH, 2) H_3O^+, 3) \text{sodalime}, \Delta} \text{benzene}$
$(D)$ $1,3,5-\text{triformylbenzene} \xrightarrow{Zn/Hg, HCl} 1,3,5-\text{trimethylbenzene}$

Which of the following groups increases the reactivity of electrophilic aromatic substitution?

Answer the following questions: What is the electrophile in the sulphonation reaction of benzene? And how is it obtained?

Which of the following products cannot be obtained in the ozonolysis of $o$-xylene?

For the given reaction:
$CH_{3}-CH=CHBr \xrightarrow[2. \text{Red hot iron tube}, 873 \text{ K}]{1. \text{NaNH}_{2}} A$ (major product)
Identify the major product $A$.