Identify the end product $(Z)$ in the sequence of the following reactions:
$C_2H_4Br_2$ $\xrightarrow[(ii) NaNH_2]{(i) Alc. KOH} X$ $\xrightarrow[873 \ K]{\text{Red hot Fe tube}} Y$ $\xrightarrow[\text{Anhy } AlCl_3, \Delta]{CH_3COCl} Z$

Explain the halogenation of benzene with the example of chlorination.

Friedel-Crafts acylation is

Nitrating mixture is

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

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 $A$.