题目

     One would have to be a fool to overlook the importance of using positive thinking for you rather than snowing negative thinking to work against you. In recent years, research in psychopharmacology(精神药理学) has proved what many people have known over the centuries: a positive attitude is good for you, good for your health, good for your wealth, good for everything.       Researchers have found that a positive attitude produces a specific chemical reaction which makes people feel better, while negative thinking results in a reduction of hormone(荷尔蒙) and shuts down th实现下列变化，一定要加入氧化剂的是A. CaCO3 → CO2B. NaCl → NaNO3C. Zn → ZnCl2D. Cl2→HCl