Write the equations for the preparation of $1-iodobutane$ from:
$(i)$ $1-butanol$
$(ii)$ $1-chlorobutane$
$(iii)$ $but-1-ene$.

(N/A) $(i)$ $CH_3CH_2CH_2CH_2OH + HI \xrightarrow{ZnCl_2} CH_3CH_2CH_2CH_2I + H_2O$
$(ii)$ $CH_3CH_2CH_2CH_2Cl + NaI \xrightarrow{\text{dry acetone (Finkelstein reaction)}} CH_3CH_2CH_2CH_2I + NaCl$
$(iii)$ $CH_3CH_2CH=CH_2 + HBr$ $\xrightarrow{\text{peroxide (Anti-Markovnikov addition)}} CH_3CH_2CH_2CH_2Br$ $\xrightarrow{NaI/\text{dry acetone}} CH_3CH_2CH_2CH_2I + NaBr$