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问题 单项选择题

一台直流电动机，其额定电压为220V，额定电流为808A，额定效率为90％，该电动机的额定功率为（）kW。

A.197.5l 

B.177.76 

C.159.98 

D.143.98

答案

参考答案：C

完形填空

阅读下面的短文．并根据短文后的要求答题。

Since 1850．the temperature of Earth’s surface has increased about 0.6°C．Scientists predict it may warm much more by the end of this century．Who’s turning up the heat? Well, it seems that we are! Some of this global warming may be natural．However，nearly all scientists now agree that most of it is due to peoples actions．Over the past 150 years, we've added huge amounts of certain gases, especially carbon dioxide（CO2）to the air．These gases can keep heat near Earth's surface，so more carbon dioxide means more heat is kept near Earth's surface．Global warming may change the weather in ways that lead to more severe storms，floods and droughts．

We add carbon dioxide to the air when we burn things, especially fossil fuels．Fossil fuels are energy sources formed from the remains of plants and animals that lived millions of years ago．Coal，oil，and natural gas are all fossil fuels．People in the United States and other countries started bunting large amounts of fossil fuels more than a century ago．The amount d fossil fuels being burned each year has been increasing worldwide．The more we burn，_____________________．

What can we do to help? Nowadays to live a low-carbon life is quite popular in the world． Low-carbon means to reduce the amount of carbon dioxide．Saving energy and reusing are the key words. In fact, even the simplest everyday activities can make our lives low-carbon．

1．What problem can global warming cause?（根据短文内容回答问题）

2．What are fossil fuels?（同上）

3．请将第一段中的划线句子翻译成汉语。

4．请根据第二段内容，将最后一个句子补充完整。

The more we bum，_____________________________________________.

5．请写出日常生活中的一种“低碳”行为（用英语写一个句子）。
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单项选择题

过去几十年来，高等教育计划招收的学生中女性所占的比例呈上升的趋势。这一点部分地可以通过以下的事实表明，即在1959年，20—21岁间的女性只有11%被招进大学，而在1981年，30%的20--21岁间的女性被招进大学。
为了评价以上的论述，对1959年和1981年的下面哪个特征进行比较最有用( )

A．20—21岁间的未被大学招收的女性的比例。

B．20—21岁间的从大学毕业的女性比例。

C．20—21岁间的被大学招收的男性比例。

D．从高中毕业的男性的比例。
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