[单项选择]Carbon monoxide, funned by the incomplete combustion of some carbonaceous material, has been a （） to humans since the domestication of fire.
A. hazard
B. dispute
C. docile
D. boost

[单项选择]The carbon price in Europe

[单项选择]Why researchers put trees in extra carbon dioxide in the first study


A. To learn whether trees can still absorb carbon dioxide under extreme conditions.
B. To get more oxygen from these trees.
C. To evaluate the maximum carbon dioxide that trees can absorb.
D. To see the growth rate of these trees.

[单项选择]

Passage 2
The molecules of carbon dioxide in the Earth’s atmosphere affect the heat balance of the Earth by acting as a one-way screen. Although these molecules allow radiation at visible wavelengths, where most of the energy of sunlight is concentrated, to pass through, they absorb some longer wave- length, infrared emissions radiated from the Earth’s surface, radiation that would otherwise be transmitted back into space. For the Earth to maintain a constant average temperature, such emissions from the planet must balance incoming solar radiation. If there were no carbon dioxide in the atmosphere, heat would escape from the Earth much more easily. The surface temperature would be so much lower that the oceans might be a solid mass of ice.
Today, however, the potential problem is too much carbon dioxide. The burning of fossil fuels and the clearing of forests have increased atmospheric carbon dioxide by about 15 percent in the last hundred years
A. 15℃
B. -18℃
C. 2.5℃
D. 9℃

[填空题]Carbon can transform into diamonds with appropriate ______.

[单项选择]The incomplete sentence of "So far so good" (Paragraph 10) can probably be used to mean ______.
A. It is good as long as I can do it
B. Until now things have gone well
C. Though until now things have gone well, I still hope to do it better
D. Though I am not so sure if all my answers are correct, I still feel OK

[单项选择]The underlined word" carbon" (Par


A. A．2) stands for_______. its intelligence and cost are beyond questionB. it is able to bear the rough environmentC. it is made as complex as the human brainD. its architecture is different from that of the present ones

[单项选择]Plants use the carbon, along with sunlight, for growth, and ___ oxygen into the atmosphere in a process known as photosynthesis.
A. relieve
B. relate
C. release
D. retain

[单项选择]It can be concluded that a concentration of carbon dioxide in the atmosphere would ______.

[单项选择]

In the atmosphere, carbon dioxide acts rather like a one-way mirror -- the glass in the roof of a greenhouse which allows the sun’s rays to enter but prevents the heat from escaping.
According to a weather expert’s prediction, the atmosphere will be 3~C warmer in the year 2050 than it is today, if man continues to burn fuels at the present rate. If this warming up took place, the ice caps in the poles would begin to melt, thus raising sea level several metres and severely flooding coastal cities. Also, the increase in atmospheric temperature would lead to great changes in the climate of the northern hemisphere, possibly resulting in an alteration of the earth’s chief food-growing zones.
In the past, concern about a man-made warming of the earth has concentrated on the Arctic because the Antarctic is much colder and has a much thicker ice sheet. But the weather experts are now paying more attention to West Antarctic, which may be affected by only
A. mainly because the levels of carbon dioxide are rising
B. possibly because the ice caps in the poles are melting
C. exclusively due to the effect of the inertia of the earth's climate
D. partly due to variations in the output of solar energy