The grey is the answer. Please thoroughly explain why. Thanks!

11) Problem 13.104: Research how a catalytic converter works. Why do you think the first five minutes or so after a car has been started are the most polluting? During the first five minutes or so the engine is relatively cold, so the exhaust gases will not fully react with the components of the catalytic converter. Remember, for almost all reactions, the rate of reaction increases with temperature. 12) You are still studying the acid-catalyzed bromination of acetone (C4COOCH3).Given the following reaction, explain how can you tell what the catalyst is? Which substance is regenerated? H3CCOCH3BrBr+H3O+H3CCOCH2Br+H3O++Br