Classify the following reactions in one of the reaction type studied in this unit. (a) CH3CH2Br+HS–→CH3CH2SH+Br– (b) (CH3)2C=CH2+HCl→(CH3)2ClC–CH3 (c) CH3CH2Br+HO–→CH2=CH2+H2O+Br– (d) (CH3)3C–CH2OH+HBr→(CH3)2CBrCH2CH3+H2O