题目内容

取异烟肼约0.2g，精密称定，置100ml的量瓶中，加水使溶解并稀释至刻度，摇匀，精密量取25ml，加水50ml、盐酸20ml与甲基橙指示剂1滴，用溴酸钾滴定液(0.01667mol/L)缓缓滴定至粉红色消失。每lml的溴酸钾滴定(0.01667mol/L)相当于mg的异烟肼(已知：滴定反应中物质的量比为：异烟肼：溴酸钾=3:2；异烟肼分子量为137.14)

A. 3.429
B. 2.018
C. 0.356
D. 0.120
E. 12.20

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When I was growing up in America, I was ashamed of my mother’s Chinese English. Because of her English, she was often treated unfairly. People in department stores, at banks, and at restaurants did not take her seriously,did not give her good service,pretended not to understand her,or even acted as if they did not hear her.My mother has realized the limitations of her English as well. When I was fifteen, she used to have me call people on phone to pretend I was she. I was forced to ask for information or even to yell at people who had been rude to her. One time I had to call her stockbroker (股票经纪人).I said in an adolescent voice that was not very convincing, “This is Mrs.Tan.”And my mother was standing beside me,whispering loudly, “Why he don’t send me cheek, already two weeks late.”And then,in perfect English I said: “I’m getting rather concerned.You agreed to send the check two weeks ago, but it hasn’t arrived.”Then she talked more loudly. “What he want I come to New York tell him front of his boss.”And so I turned to the stockbroker again, “I can’t tolerate any more excuses. If I don’t receive the check immediately,I am going to have to speak to your manager when I am in New York next week.”The next week we ended up in New York. While I was sitting there redfaced, my mother, the real Mrs.Tan, was shouting to his boss in her broken English.When I was a tennager, my mother’s broken English embarrassed me. But now, I see it differently. To me, my mother’s English is perfectly clear, perfectly natural. It is my mother tongue. Her language, as I hear it, is vivid, direct, and full of observation and wisdom. It was the language that helped shape the way I saw things, expressed ideas, and made sense of the world. From Paragraph 2, we know that the author was （）

A. good at pretending
B. rude to the stockbroker
C. ready to help her mother
D. unwilling to phone for her mother

医疗事故的主观方面是

A. 造成患者人身损害
B. 过失
C. 违法行为和损害结果之间有因果关系
D. 实施了违反卫生管理法律、行政法规、部门规章和诊疗护理规范、常规的行为
E. 医疗机构和医务人员

出口到欧盟国家的货物纸箱包装有什么绿色环保的要求

作为评价投资方案的基本标准，资金的时间价值往往以利息率来表示。( )

A. 对
B. 错