试题与答案

(2010年济宁模拟)根据巴耳末公式,指出氢原子光谱在可见光范围内波长最长的两条

题型:计算题

题目:

(2010年济宁模拟)根据巴耳末公式,指出氢原子光谱在可见光范围内波长最长的两条谱线所对应的n,它们的波长各是多少?氢原子光谱有什么特点?

答案:

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题型:阅读理解

A small piece of fish each day may keep the heart doctor away. That's the finding of an extensive study of Dutch men in which deaths from heart disease were more than 50 percent lower among those who consumed(消费) at least an ounce of salt water fish per day than those who never ate fish.

The Dutch research is one of three human studies that give strong scientific backing to the long-held belief that eating fish can provide health benefits, particularly to the heart.

Heart disease is the number-one killer in the United States , with more than 550, 000 deaths occurring from heart attacks each year . But researchers previously have noticed that the incidence (发生率)of heart disease is lower in cultures that consume more fish than Americans do. There are fewer heart disease deaths, for example, among the Eskimos of Greenland, who consume about 14 ounces of fish a day, and among the Japanese, whose daily fish consumption averages more than 3 ounces.

During the next two decades, 78 of the men died from heart disease. The fewest deaths were among the group who regularly ate fish, even at levels far lower than those of the Japanese or Eskimos. This relationship was true regardless of other factors such as age , high blood pressure , or blood cholesterol (胆固醇) levels .

64. Which of the following is NOT true according to the passage?

A. The Dutch research has proved that eating fish can help to prevent heart disease.

B. There is a low incidence of heart disease in countries like Japan and Greenland.

C. Among all the diseases heart disease is the most dangerous in America.

D. Heart doctors won’t call your house so long as you keep eating fish each day.

65. The underlined phrase “this relationship” refers to the connection between _______ and the incidence of heart disease.

A. the amount of fish eaten   B. regular fish-eating

C. the kind of fish eaten          D. people of different regions

66. The passage is mainly about __________________.

A. the high incidence of heart disease in some countries

B. the changes in people’s diet in the United States

C. the daily fish consumption of people in different cultures  

D. the effect of fish eating regularly on people’s health

67. How many lives could probably be saved each year in the United States by eating fish according to the Dutch study?

A. 550, 000.              B. 110,000.      C. 275,000.            D. 852.

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题型:单项选择题

根据《地铁设计规范》GB50157—2013,下列关于地铁车站排烟风机耐高温性能的说法中,错误的是:()。

A.地上设备与管理用房,排烟风机应保证在280℃时能连续有效工作0.5h

B.地上车站公共区,排烟风机应保证在250℃时能连续有效工作1h

C.区间隧道,排烟风机应保证在250℃时能连续有效工作1h

D.高架车站公共区,排烟风机应保证在280℃时能连续有效工作1h

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