How can the following conversions be carried out?
$(i)$ Propene to propan$-1-$ol
$(ii)$ Ethanol to but$-1-$yne
$(iii)$ $1-$Bromopropane to $2-$bromopropane
$(iv)$ Toluene to benzyl alcohol
$(v)$ Benzene to $4-$bromonitrobenzene
$(vi)$ Benzyl alcohol to $2-$phenylethanoic acid
$(vii)$ Ethanol to propanenitrile
$(viii)$ Aniline to chlorobenzene
$(ix)$ $2-$Chlorobutane to $3,4-$dimethylhexane
$(x)$ $2-$Methyl$-1-$propene to $2-$chloro$-2-$methylpropane
$(xi)$ Ethyl chloride to propanoic acid
$(xii)$ But$-1-$ene to $n-$butyliodide
$(xiii)$ $2-$Chloropropane to $1-$propanol
$(xiv)$ Isopropyl alcohol to iodoform
$(xv)$ Chlorobenzene to $p-$nitrophenol
$(xvi)$ $2-$Bromopropane to $1-$bromopropane
$(xvii)$ Chloroethane to butane
$(xviii)$ Benzene to diphenyl
$(xix)$ tert-Butyl bromide to isobutyl bromide
$(xx)$ Aniline to phenylisocyanide

$(i)$ Propene $\xrightarrow{HBr/\text{Peroxide}}$ $1-$Bromopropane $\xrightarrow{Aq. KOH, \Delta}$ Propan$-1-$ol.
$(ii)$ Ethanol $\xrightarrow{PBr_3}$ Bromoethane $\xrightarrow{Mg, \text{ether}}$ Ethylmagnesium bromide $\xrightarrow{\text{Ethylene oxide}, H_3O^+}$ Butan$-1-$ol $\xrightarrow{P/I_2}$ $1-$Iodobutane $\xrightarrow{alc. KOH}$ But$-1-$ene $\xrightarrow{Br_2/CCl_4}$ $1,2-$Dibromobutane $\xrightarrow{NaNH_2}$ But$-1-$yne.
$(iii)$ $1-$Bromopropane $\xrightarrow{alc. KOH}$ Propene $\xrightarrow{HBr}$ $2-$Bromopropane.
$(vii)$ Ethanol $\xrightarrow{PBr_3}$ Bromoethane $\xrightarrow{KCN, \text{ethanol}}$ Propanenitrile.
$(ix)$ $2-$Chlorobutane $\xrightarrow{2Na, \text{dry ether}}$ $3,4-$Dimethylhexane.
$(x)$ $2-$Methylpropene $\xrightarrow{HCl}$ $2-$Chloro$-2-$methylpropane.
$(xi)$ Ethyl chloride $\xrightarrow{KCN}$ Propanenitrile $\xrightarrow{H_3O^+}$ Propanoic acid.
$(xii)$ But$-1-$ene $\xrightarrow{HBr, \text{Peroxide}}$ $1-$Bromobutane $\xrightarrow{NaI, \text{acetone}}$ $1-$Iodobutane.
$(xiii)$ $2-$Chloropropane $\xrightarrow{alc. KOH}$ Propene $\xrightarrow{HBr, \text{Peroxide}}$ $1-$Bromopropane $\xrightarrow{Aq. KOH}$ Propan$-1-$ol.
$(xiv)$ Isopropyl alcohol $\xrightarrow{[O]}$ Acetone $\xrightarrow{I_2/NaOH}$ Iodoform.
$(xvi)$ $2-$Bromopropane $\xrightarrow{alc. KOH}$ Propene $\xrightarrow{HBr, \text{Peroxide}}$ $1-$Bromopropane.
$(xvii)$ Chloroethane $\xrightarrow{2Na, \text{dry ether}}$ Butane.
$(xix)$ tert-Butyl bromide $\xrightarrow{alc. KOH}$ $2-$Methylpropene $\xrightarrow{HBr, \text{Peroxide}}$ Isobutyl bromide.