《中华人民共和国水污染防治法》规定：禁止在生活饮用水地表水源 ( )内新建、扩建与供

阅读下文,从各小题所给的四个选项中选出能回答所提问题或完成所给句子的最佳答案.

     The World Expo has a longer history. This is about some of the World Expos.

1851 The first Expo, also called "The Great Exhibition" , was held in Hyde Park, London. The key

exhibits of the first Expo included the early fax machines and some other inventions.  So the first Expo

had great influence on many fields of society.

1886 The Statue of Liberty(自由女神像)  came to the World's Fair. French people sent it as a gift to

the US in 1886. The statue was on show at the Expo in Philadelphia, US.

1889 France held the Expo in Paris. The famous Eiffel Tower was built for the Expo. It is 324 meters

high and once the tallest structure in the world.

1893 The World's Fair was held in Chicago, US. For the first time, it used electricity. It meant the

beginning of a modern revolution(革命).

1904 China  first  took part  in the  World's Fair in Saint  Louis, US.  Besides  porcelain( 瓷器)  and

handicrafts, China also showed Beijing Opera and tea culture.

1933 This World's  Fair  was held  in Chicago with the theme of  "Century  of  Progress".  Themed

exhibitions started from this fair and later became a key part of all World's Fairs.

1970 The world Expo was held in Japan. It was the first Expo in Asia. Countries shared different ideas

about technological progress at the Expo. 77 countries took part in the Fair and discussed how to make

a peaceful future.

2000 The World's Fair was held in Germany. Earlier World Expos were most about technology. This

one tried to find solutions for global problems, like how to protect the environment.

1.  From above we can see at least________ World Expos were held in Europe. 

A. Two.    

B. Three.    

C. Four.    

D. Five.

2. According to this article, which city held the World Expo twice?

A. London.            

B. Paris.

C. Saint Louis.        

D. Chicago.

3. Which of the following is TRUE?      

A. The Great Exhibition was held in the eighteenth century.

B. The World Expo always has its theme.

C. China first held the World Expo successfully in 1904.

D. Countries discussed how to make a peaceful future in the World's Fair in Japan.

探究实验．

小枫发现：夏天，做熟的食品很快就会腐败变质，俗称“变馊了”．这是什么原因呢？原来，做熟的食品里生出了无数的细菌．食品中的这些细菌是从哪里来的呢？是由食品自然产生，还是来自空气？小枫认为应该是来源于空气，对此，小枫设计了实验：小枫将刚煮沸的新鲜、清澈的肉汤分别装入甲、乙两个玻璃瓶（用开水煮过）里，然后把甲瓶的瓶口用无菌棉花团塞严，把乙瓶的瓶口敞开，然后放在相同的环境中，静置观察．观察发现，乙瓶内的肉汤很快就腐败变质了；而甲瓶中的肉汤没有腐败．由此，小枫认为，使肉汤腐败变质的细菌来自空气．

根据上述材料回答问题：

（1）小枫提出的问题是______．

（2）小枫作出的假设是______．

（3）为什么是刚煮沸的肉汤，而不是晾冷后的？______．

（4）为什么玻璃瓶要用开水煮过、棉花团要无菌的？______．

（5）实验中小枫控制的变量是______．

（6）小枫得出的结论是______．

在“测定小灯泡电功率”的实验中，灯泡的额定电压为2.5V ，灯丝的电阻约为8Ω。

(1)在连接电路时，开关应处于                   状态。

(2)请用笔画线代替导线，把图10电路元件连接成实验电路。（连线不得交叉）

(3)请在右方框内画出该电路的电路图。

下列说法正确的是(　　)

A．前四周期中，原子最外层为1个电子的元素有5种

B．Fe²⁺的价电子排布为3d⁶

C．2p轨道上有1个未成对电子的原子与3p轨道上有1个未成对电子的原子化学性质相似

D．AB₃型分子的中心原子A采取sp³杂化

由于近年来国际贸易的快速发展，国际分工日益明显，国家采购急剧扩大以及世界经济的一体化，国际物流正成为现代物流的研究重点之一。