Which are free radical reactions
I.CH3−CH=CH2+HBrPeroxide−−−−−→CH3−CH2−CH2BrII.CH3−CH=CH2+HBr→CH3−CHBr−CH3III.CH3−CH=CH2+Cl2→ClCH2−CH=CH2IV.CH3−CH3+Cl2→ClCH2−CH3