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问题 单项选择题

世界上最早的一篇专门论述教育、教学问题的论著是( )。

A．《论语》
B．《学记》
C．《理想国》
D．《雄辩术原理》

答案

参考答案：B

解析： 我国的《学记》是世界上最早的一篇专门论述教育、教学问题的论著。

多项选择题

计算机按照操作对象可以分为（）。

A.模拟计算机

B.通用计算机

C.数字计算机

D.专用计算机
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问答题

If a heavy reliance on fossil fuels makes a country a climate ogre, then Denmark — with its thousands of wind turbines sprinkled on the coastlines and at sea — is living a happy fairy tale.
Viewed from the United States or Asia, Denmark is an environmental role model. The country is "what a global warming solution looks like," wrote Frances Beinecke, the president of the Natural Resources Defense Council, in a letter to the group last autumn. About one-fifth of the country’s electricity comes from wind, which wind experts say is the highest proportion of any country.
But a closer look shows that Denmark is a far cry from a clean-energy paradise. The building of wind turbines has virtually ground to a halt since subsidies were cut back. Meanwhile, compared with others in the European Union, Danes remain above-average emitters of the greenhouse gas carbon dioxide. For all its wind turbines, a large proportion of the rest of Denmark’s power is generated by plants that burn imported coal.
The Danish experience shows how difficult it can be for countries grown rich on fossil fuels to switch to renewable energy sources like wind power. Among the hurdles are fluctuating political priorities, the high cost of putting new turbines offshore, concern about public acceptance of large wind turbines and the volatility of the wind itself.
"Europe has really led the way," said Alex Klein, a senior analyst with Emerging Energy Research, a consulting firm with offices in Cambridge, Massachusetts.
Some parts of western Denmark derive 100 percent of their peak needs from wind if the breeze is up. Germany and Spain generate more power in absolute terms, but in those countries wind still accounts for a far smaller proportion of the electricity generated. The average for all 27 European Union countries is 3 percent.
But the Germans and the Spanish are catching up as Denmark slows down. Of the thousands of megawatts of wind power added last year around the world, only 8 megawatts were installed in Denmark.
If higher subsidies had been maintained, he said, Denmark could now be generating close to one-third — rather than one-fifth — of its electricity from windmills.
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