(A) When $1-$bromopropane reacts with alcoholic$\mathrm{KOH}$, the bromine with the alpha H (hydrogen from the carbon alongside the carbon fortified with useful gathering) is eliminated and subsequently forms $1-$propene. 

(B) When $1-$Bromo propane reacts with $\mathrm{alc} \mathrm{KCN}$ it will form butanenitrile. 

(C)  When akyl halide reacts with silver nitrite, nitroalkane is formed because the bond between $\mathrm{Ag}-\mathrm{OAg}-\mathrm{O}$ is covalent, the lone pair on nitrogen acts as an attacking site for nucleophilic substitution.  

(D) When $1-$bromopropane reacts with silver acetate, propyl ethanoate and silver bromide are formed.