语音知识（共5小题，每小题1分，满分5分） 从A、B、C、D四个选项中，找出其划

若x²+y²+4x-6y+13=0，则代数式2x²+2y²的值是（　　）

A．25

B．26

C．27

D．2008

Waste paper shouldn't ______ everywhere. It's our duty to keep our classroom clean. [ ]

A. be thrown

B. throw

C. is thrown

D. are thrown

熟读第一单元训练检测案（一）第一节（必修1）课文并完成填空练习

    Anne made her diary her best friend because she had

no friend who could understand what she was going

1. ______and she wanted a friend.

    Anne lived in Amsterdam in the Netherlands

2._______World War ?. Her family had to hide or they

would be 3._______by the German Nazis because her

family was Jewish. They 4. ______away for more than

two years. During that time her only true friend was her

diary. She didn't want to set 5. ______a series of facts in

a diary as most people did,but she wanted the diary itself

to be her friend. She even 6. _______her diary Kitty.

       In her diary,she wondered if it was because she hadn't

been able to go 7. _______for so long that she had grown

so 8._____about everything to do with nature. She

could well remember that there was a time 9._______a

deep blue sky,the song of the birds,moonlight and flowers

could never have 10. ______her spellbound.

根据粘土中矿物含量的不同，粘土大体分为（）。

A、2类

B、3类

C、4类

D、5类

下面正确描述一级价格歧视的福利情况的是（）.

A.消费者可以通过自我选择来尽可能地提高自身的效用，得到最大化的满足

B.社会总福利等同于完全竞争市场上的社会总福利，没有净福利损失

C.生产者不能完全把消费者剩余转化为生产者利润，只能占有部分的消费者剩余；

D.与完全竞争市场相比，是缺乏效率的，因为导致社会福利的无谓损失。