How would you convert the following compounds into benzene?
$(i)$ Ethyne $(ii)$ Ethene $(iii)$ Hexane

(N/A) $(i)$ Benzene from ethyne:
$3CH \equiv CH \xrightarrow[\text{Polymerisation}]{\text{Red hot Fe, } 873 \ K} \text{Benzene}$
$(ii)$ Benzene from ethene:
$CH_2=CH_2$ $\xrightarrow[\text{Bromination}]{\text{Br}_2(\text{CCl}_4)} CH_2Br-CH_2Br$ $\xrightarrow[\text{Dehydrobromination}]{\Delta, \text{KOH (alc.)}} CH_2=CHBr$ $\xrightarrow[\text{NaNH}_2, \text{NH}_3(l)]{196 \ K} HC \equiv CH$ $\xrightarrow[\text{Polymerisation}]{\text{Red hot Fe, } 873 \ K} \text{Benzene}$
$(iii)$ Benzene from hexane:
$CH_3CH_2CH_2CH_2CH_2CH_3$ $\xrightarrow[\text{Cyclization, H}_2]{\text{Cr}_2\text{O}_3/\text{Mo}_2\text{O}_3/\text{V}_2\text{O}_5, 773 \ K, 10-20 \ \text{atm.}} \text{Cyclohexane}$ $\xrightarrow[\text{-3H}_2]{\text{Aromatization}} \text{Benzene}$