A)`SN^2` - Inversion of configuration as rear attack of `Nu^-`causes inversion B)`SN^1` – Order of reactivity is RI > RBr > RCI C) `E_1 `- Reacemization (retention of inversion) is possible order in RI > RBr > RCI `SN^1`- Two step mach, step-I-Carbocation formation, `SN^1 & E_1` - mechanisms are similar except last step D) `E_2` - mechanism also similar to `SN^2` but carbocation also form
