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问题 选择题

下列有关海水综合利用的说法正确的是（　　）

A．海水中含有钾元素，只需经过物理变化就可以得到钾单质

B．海水蒸发制海盐的过程中只发生了化学变化

C．从海水中可以得到NaCl，电解熔融NaCl可制备Cl2

D．从海带中提取碘单质的过程不涉及氧化还原反应

答案

答案：C

阅读理解

根据短文内容，完成下列句子，每空一词。

     Hello, everyone! My name is Wang Haibo. My English name is Daniel. I live in Yibin.

     Look! This is my school. It is called Yuejiang Secondary School. It is an old school, but it is very big

and nice. There are a lot of trees and flowers in it. And the teachers and students are all very nice. I like

my school very much.

     There is a big playground in our school. On Mondays and Wednesdays, I like playing football there

with  my  good  friends. But on  Tuesdays and  Thursdays I go to the  Reading Club after school. I like

reading books. I can learn a lot from the books. Do you like reading?

1. Wang Haibo's ________ ________ is Daniel.

2. Yuejiang Secondary School is an ________ ________.

3. The school is very nice because there are many ________ and ________ in it.

4. Daniel plays football every ________ and ________.

5. Daniel likes ________ and playing ________.

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单项选择题

对于两种物品，如果一种物品价格的上升会引起另一种物品需求的增加，则这两种物品被称为替代品；如果一种物品价格的上升会引起另一种物品需求的下降，则这两种物品被称为互补品。
根据上述定义，下列属于互补品的是______。

A．春运期间，由于火车票“一票难求”，不少人转而乘坐飞机回家
B．随着数码相机的使用越来越广泛，胶卷这一产品正逐渐退出历史舞台
C．在物价不断上涨的今天，由于牛奶的价格上升得较快，许多人转而购买奶粉
D．由于中国联通与iphone4开展了合约计划政策，购买iphone4的用户只能选择联通的通信服务
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