下列有关实验的评价正确的是（　　）A. 点燃某可燃物，在火焰上罩一个冷而干燥的烧杯，烧杯的内壁有水雾

生命伦理学在哪项基础上形成的

A、临床医学与医德学

B、伦理学与医学

C、生命质量论与生命价值论

D、伦理学与生命质量论

E、伦理学与生命科学

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规定的观察期内某病患者中因该病而死亡的频率是

A.发病率

B.患病率

C.某病病死率

D.某病死亡率

E.治愈率

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The research carried out in eight countries______.

A．reveals the relationship between sleep problems and age

B．provides evidence that lack of sleep affects people"s health

C．puts forward the theory that sleep problems are a kind of disease

D．proves that sleep problems will lead to smoking and poor diet

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According to the passage, what problem does the recent research find？

A．Sleep shortage has become a worldwide problem.

B．Developed nations don"t pay enough attention to sleep.

C．Sleep problems are more serious in developing countries.

D．Lack of sleep is more obvious in developed countries.

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American students usually get their high school diploma at the age of______.

A．12

B．17

C．20

D．24

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What responsibilities do states have concerning education？

A．They must decide what certificate teachers should have.

B．They must pick out the suitable textbooks for students.

C．They must make sure every child can receive education.

D．They must provide enough funds for their schools.

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