锁骨下静脉插管进针点在胸锁乳突肌外侧缘与锁骨上缘所形成夹角平分线上距该点多少cm：（

下面是小学一年级上册教材中拼音教学“b，p，m，f”一课的课文内容（此前一课为韵母“i，u，ü”），如果你来设计课堂教学，你打算为这堂课设计一则怎样的课堂导入语？ （5分）

中度吸入性损伤损伤范围深达()

A．鼻咽部

B．喉部

C．气管隆突以上

D．支气管

E．肺泡

单果

化学对提高人类生活质量和促进社会发展具有重要作用，下列说法正确的是（   ）

①研发安全特效药物，有利于抵御人类疾病

②新型复合材料的使用，使手机、电脑等电子产品更轻巧、更美观

③规范食品添加剂生产和科学使用，有利于保障人体健康和生命安全

④用聚氯乙烯代替聚乙烯作食品包装袋，有利于节约使用成本

A．①②③

B．②④

C．①③④

D．①②③④

Under pressure from animal welfare groups, two national science teachers associations have adopted guidelines that ban classroom experiments harming animals. The National Association of Biology Teachers and the National Science Teachers Association hope to end animal abuse in elementary and secondary schools and, in turn, discourage students from mishandling animals in home experiments and science fair projects.

Animal welfare groups are apparently most concerned with high school students experimenting with animals in extracurricular projects. Barbara Orlans, President of the Scientists’ Center for Animal Welfare, said that students have been performing surgery at random, testing known poisonous substances, and running other pathology experiments on animals without even knowing normal physiology.At one science fair, a student cut off the leg and tail of a lizard to demonstrate that only the tail can regenerate, she said. In another case, a student bound sparrows, starved them and observed their behavior.

"The amount of abuse has been quite horrifying," Orlans said.Administrators of major science fairs are short-tempered over the teachers’ policy change and the impression it has created. "The teachers were sold a bill of goods by Barbara Ortans," said Thurman Grafton, who heads the rules committee for the International Science and Engineering Fair. "Backyard tabletop surgery is just nonsense. The new policies throw cold water on students’ inquisitiveness," he said.

Grafton said he wouldn’t deny that there hasn’t been animal abuse among projects at the international fair, but he added that judges reject contestants who have unnecessarily injured animals. The judges have a hard time monitoring local and regional fairs that may or may not choose to comply with the international fair’s rules that stress proper care of animals, Grafton said.

He said that several years ago, the Westinghouse Science Talent Search banned harmful experiments to animals when sponsors threatened to cancel their support after animal welfare groups lobbied for change.

The teachers adopted the new policies also to fend off proposed legislation--in states including Missouri and New York--that would restrict or prohibit experiments on animals.

Officials of the two teachers organizations say that they don’t know how many animals have been abused in the classroom. On the one hand, many biology teachers are not trained in the proper care of animals, said Wayne Moyer, executive director of the biology teachers’ association. On the other, the use of animals in experiments has dropped in recent years because of school budget cuts. The association may set up seminars to teach better animal care to its members. (414 words)

Notes: pathology 病理学。lizard 蜥蜴。tabletop 桌面。short-tempered 脾气急躁的。lobby for 游说支持。fend off 躲开。

The title which best expresses the content of the text is（）

A. Science Teachers to Ban Testing Harmful to Animals

B. Teachers’ Policy Change in Experiment on Animals

C. The New Policies of Banning Harmful Experiments to Animals

D. The Importance of Prohibiting Harmful Experiments on Animals