Classify the following reactions in one of the reaction type studied in this unit
(i) `CH_(3)CH_(2)Br+SH^(-) rarr CH_(3)CH_(2)SH+Br^(-)`
(ii) `(CH_(3))_(2)C=CH_(2)+HCl rarr (CH_(3))_(2)C(Cl)CH_(3)`
(iii) `(CH_(3))_(3)C CH_(2)OH+HBr rarr (CH_(3))_(2)CBrCH_(2)CH_(3)`
(iv) `CH_(3)CH_(2)Br+HO^(-) rarr CH_(2)=CH_(2)+H_(2)O+Br^(-)`