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问题 单项选择题

基本预备费的计费基数是（）。

A.设备及工器具购置费

B.建筑安装工程费

C.设备及工器具购置费+建筑安装工程费

D.设备及工器具购置费+建筑安装工程费+工程建设其它费用

答案

参考答案：D

阅读理解

The most important use of drifting (漂流) bottles is to find ocean currents. When the position and direction of currents are known, ships can use the forward movement of a current or stay away from currents that would carry them off their course. Benjamin Franklin was one of the first to use bottles in the study of currents. He wondered why British mall ships needed a week or two longer than U.S. ships needed in order to cross the Atlantic Ocean. Franklin thought the Gulf Stream (墨西哥湾流) might explain this difference.

Franklin talked with captains of U.S. ships. He found that they knew each turn of the Gulf Stream. They used the current in every possible way. From his talks with the captains. Franklin made his first map of the Gulf Stream. Then he checked his map by using sealed (密封的) bottles. The map that he finally made is still used, with only a few changes, today. 

小题1: Why are drifting bottles used?

A．To determine the position of a ship

B．To carry message across the ocean

C．To predict the direction of a ship.

D．To find the direction of a current小题2:What led Franklin to talk with U.S. captains?

A．U.S. ships were longer than British ones.

B．British ships could sail the Atlantic faster than U.S. ones.

C．U.S captains knew more about maps.

D．U.S. ships could sail the Atlantic faster than U.S. ones.小题3:What did Franklin make after his talks with U.S. captains?

A．A map of the Atlantic Ocean.

B．A map of the Gulf Stream..

C．A map of ocean currents.

D．A map of his first voyage.小题4:What did Franklin do in order to make an exact map?

A. He compared his own map with other maps

B. He talked with many U.S. captains.

C. Both B and C.

D. He used drifting bottles to check his map.
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问答题

某研究性学习小组对铝热反应（以Al和Fe2O3反应为例）实验进行研究．已知Al、Al2O3、Fe、Fe2O3的熔点、沸点数据如表所示：

  物质    Al  A12O3    Fe  Fe2O3
  熔点/℃    660    2054    1535    1565
  沸点/℃    2467    2980    2750----
试回答下列问题：

（1）铝热反应是氧化还原反应，在反应中金属铝表现出______性 （填“氧化”或“还原”）．

（2）某同学根据以上数据推测，铝热反应所得到的熔融物中应含有铁、铝两种金属．如设计一个简单的实验方案证明该熔融物中含有金属铝，则实验所需用的试剂为______，可观察到的实验现象是______．

（3）另一同学推测铝热反应得到的熔融物中还含有Fe2O3，他设计了如下方案来验证：

取一块该熔融物投入到少量稀硫酸中，反应一段时间后，向反应后的混合液中滴加物质甲的溶液，观察溶液颜色的变化，即可证明熔融物中是否含有Fe2O3．则

①物质甲是______ （填化学式）．

②该同学的实验方案是否合理？答：______ （填“合理”或“不合理”）．

（4）把l5.12g Fe、Fe2O3和Al的混合物与0.5L 2mol-L-1稀硫酸（足量）充分反应，生成氢气n mol．则

①用浓硫酸配制0.5L 2mo1-L-1的稀硫酸需要的玻璃仪器有烧杯、500mL容量瓶、量筒和______、______．

②n的取值范围是______．

③向反应后的混合溶液中滴加NaOH溶液，当产生沉淀的量达到最大时，参加反应的NaOH的物质的量为______ mol．
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