Be sure to answer all parts. explain why the addition of hbr to alkenes a and c is regioselective, forming addition products b and d, respectively.8addition to alkene a is regioselective because: alkene a forms a primary carbocation, which is always more stable than a secondary carbocation. alkene a forms a resonance stabilized carbocation on the c closest to the o atom. alkene a forms an inductively destabilized carbocation on the c closest to the o atom. the br atom is less crowded on a primary carbon than on a secondary carbon. addition to alkene c is regioselective because: alkene c forms a secondary carbocation, which is always more stable than a primary carbocation. the br atom is less crowded on the carbon that is farther away from the cooch3 group. alkene c forms a carbocation that is resonance stabilized by the cooch3 group. alkene c forms a carbocation on the c farthest from the inductively destabilizing cooch3 group.