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问题 选择题

下列变化中，必须加入氧化剂才能发生的是                                           （   ）

A．Cl2→HCl

B．NaCl→Cl2

C．Fe2＋→Fe3＋

D．NaHCO3→CO2

答案

答案：C

阅读理解
阅读下面的短文，从文后方框中选择恰当的句子填入文中空白处
A. These countries are found in much of Africa, South America and parts of Asia.
B. These people don't have enough food to eat and they live in poor housing.
C. That may not sound much, but it's about 14,000 people per hour.
D. But in the developing countries, many women have five or more children.
E. It could hurt the environment and increase the number of poor people.
     When you read this sentence, the population of the earth has grown by 10 people. (1)_____
     Most of these new people are born in developing countries. (2)_____
     In the developed countries of Europe and North America, the population is growing very slowly. This is because
women in these countries have, on average(平均), only one or two children. (3)_____
     In the developing countries, more than one billion people already live below the poverty line (贫困线). 
     (4)_____ Children get little or no time at school and suffer from many kinds of diseases.
     The UN has said that the world's population will reach 12.5 billion people by the year 2100. If the number makes your
head spinning(眩晕), you're not alone. Many experts are worrying that so fast population growth could have very bad
results. (5)_____
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判断题

南京位于南方地区，属于亚热带湿润地区。[ ]
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