题目

When it was difficult for actor Michael Doresey to get anyone to hire him, he decided to ______ a part in a soap opera as a woman. A. try out for             B. live up to           C. stand up for             D. have power over 答案：A18．下列实验不能成功的是（　　）A．用水来区分氯化钠固体和硝酸铵固体B．用酚酞试剂检验氢氧化钠溶液是否变质C．用燃着的木条鉴别氧气和二氧化碳D．用肥皂水鉴别硬水和软水