Provide the conversion for the following:
$(i)$ Formaldehyde to Butan$-1-$ol
$(ii)$ $1-$Bromopropan$-2-$one from Isopropyl alcohol

(N/A) $(i)$ Formaldehyde $(HCHO)$ reacts with propylmagnesium bromide $(CH_3CH_2CH_2MgBr)$ in the presence of dry ether to form an addition product,which upon hydrolysis yields butan$-1-$ol $(CH_3CH_2CH_2CH_2OH)$.
$(ii)$ Isopropyl alcohol $(CH_3CH(OH)CH_3)$ is oxidized using $CrO_3$ or $Cu$ at $573 \ K$ to form acetone $(CH_3COCH_3)$. Acetone then undergoes $\alpha-$bromination with $Br_2$ to yield $1-$bromopropan$-2-$one $(BrCH_2COCH_3)$.