If by Hollywood Killer you're referring to DD Clark and Carol M. Bundy then they would lure prostitutes and young teenage girls to have sexual intercourse and shoot them shortly after. Some he decapitated and some he would procede to having sexual intercourse even after they were dead (necrophilia). He would dispose of the bodies out in the open.
By stopping using harmful chemicals
Answer:Not enough info
Explanation: Please provide choices and I will explain.