下列表述与化学用语对应且正确的是( ) A.CO2的比例模型: B.氢化铵(N

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问题:

下列表述与化学用语对应且正确的是(  )

A.CO2的比例模型:

B.氢化铵(NH4H)电子式:

C.

的名称:2,3-二甲基-4-乙基己烷

D.乙酸乙酯的水CH3COOCH2CH3+H218

△ CH3COOH+CH3CH218OH

考点:电子式的书写比例模型球棍模型
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根据土地利用总体规划,()不应当划入基本农田保护区。

A.铁路、公路等交通沿线的耕地

B.城市和村庄周边的耕地

C.集镇建设用地区周边的耕地

D.需要退耕还林的耕地

E.需要退耕还牧、还湖的耕地

题型:选择题

青蛙通过皮肤呼吸所得的氧,大约占吸氧总量的( )

A.30%

B.80%

C.50%

D.40%

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创新的概念是由美国经济学家熊彼特提出来的,它是指企业家对生产要素进行新的组合,它包括的五个方面内容中,属市场创新的是()。

A.引进新产品

B.开辟新市场

C.采用新的生产方法

D.获取原料的新来源

E.采用新的企业组织形式

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Last night’s meteor (流星) shower left many people in the community dissatisfied and demanding answers. According to Gabe Rothschild, Emerald Valley’s mayor, people gathered in the suburbs of the city, carrying heavy telescopes, expecting to watch the brightly burning meteors passing through the sky. What they found instead was a sky so brightened by the city’s lights that it darkened the light of the meteors passing overhead.

“My family was so frustrated,” admitted town resident Duane Cosby, “We wanted to make this an unforgettable family outing, but it turned out to be a huge disappointment.”

Astronomers—scientists who study stars and planets—have been complaining about this problem for decades. They say that light pollution prevents them from seeing objects in the sky that they could see quite easily in the past. They call on people and the government to take measures to fight against it.

There is yet a population besides professional and amateur star observers that suffers even more from light pollution. This population consists of birds, bats, frogs, snakes, etc. For example, outdoor lighting severely affects migrating (迁徙的) birds. According to the International Dark-Sky Association, “100 million birds a year throughout North America die in crashes with lighted buildings and towers.”

Countless more animal casualties (伤亡) result from the use of artificial lighting. Clearly, people enjoy the benefits of lighting their evenings. But some scientists think it can be harmful for humans, too. They worry that exposure to light while sleeping can increase a person’s chances of getting cancer.

Emerald Valley is only one community that is becoming aware of the negative effects of light pollution. For years, Flagstaff, Arizona, has enforced lighting regulations in its city in order to assist astronomers at the Lowell Observatory. Similar efforts have been made worldwide, and a movement is underway to remind us to turn off lights when we are not using them, so that other creatures can share the night.

小题1:It happened last night that _____.

A.the city’s lights affected the meteor watching

B.the meteors flew past before being noticed

C.the city light show attracted many people

D.the meteor watching ended up a social outing小题2:What do the astronomers complain about?

A.Meteor showers occur less often than before.

B.Their observation equipment is in poor repair.

C.Light pollution has remained unsolved for years.

D.Their eyesight is failing due to artificial lighting.小题3:What is the author concerned about according to Paragraph 4?

A.Birds may take other migration paths.

B.Animals’ living habits may change suddenly

C.Varieties of animals will become sharply reduced

D.Animals’ survival is threatened by outdoor lighting.小题4:Lighting regulations in Flagstaff, Arizona are put into effect to _____.

A.lessen the chance of getting cancer

B.create an ideal observation condition

C.ensure citizens a good sleep at night

D.enable all creatures to live in harmony小题5:What message does the author most want to give us?

A.Saving wildlife is saving ourselves.

B.Great efforts should be made to save energy.

C.Human activities should be environmentally friendly.

D.New equipment should be introduced for space study..

题型:选择题

不属于国际证券融资方式的是()。

A.外国投资者直接投资本国企业

B.国际期权融资

C.本国企业到海外筹资

D.国际债券融资

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