$\underset{A}{\mathop{PhF}}\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\underset{B}{\mathop{PhCl}}\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\underset{C}{\mathop{PhBr}}\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\underset{D}{\mathop{PhI}}\,$
$(i)$ $C{H_3} - \mathop C\limits^ + H - C{H_3}$
$(ii)$ $C{H_3} - \mathop C\limits^ + H - O - C{H_3}$
$(iii)$ $C{H_3} - \mathop C\limits^ + H - CO - C{H_3}$



$(A)\,\,CH_3CH_2CH_2Br + KOH \rightarrow CH_3CH CH_2 + KBr + H_2O$
