下颌牙列中牙周膜面积最大的是（） A.第三磨牙 B.第二磨牙 C.第一磨牙 D.第二

阅读理解。

     My name is Qing Min. I'm a middle school student. I am studying in No.1 Middle School. My school isn't big, but I like it very much.

     In my school there are eighteen classes. There are about fifty students in every class. We have twenty-seven teachers. I'm in Class 4,Grade 8.In my classroom there are twenty-six desks and fifty-two chairs. There's a map of China and a map of the world on the wall. My classroom is big and clean.

     There are twenty-eight boys and twenty-four girls in my class. We have English, Chinese, math and five other subjects. Every morning some of us come to school by bus; some get to school by bike, but sometimes I come to school on foot. My English teacher often says, " Please    be careful when you come to school by bike. " He is a good teacher. We like him very much. I love my school, because our teachers are very friendly to us.

根据短文内容判断正（T）、误（F） 。

( )1. I like my school because it's No.1 Middle School.

(     )2. There are fifty-two students in Class 4,Grade 8.

(     )3. There are two maps on the wall of Class 4 , Grade 8.

(     )4. I have ten subjects at school.

(     )5. All the students walk to school.

设O为坐标原点，曲线x²＋y²＋2x－6y＋1＝0上有两点P、Q，满足关于直线x＋my＋4＝0对称，又满足·＝0.

(1)求m的值；

(2)求直线PQ的方程．

市场的三大构成要素同时决定着市场的（）。

水露点越低，越容易析出水。

对于世界贸易组织争端解决机构的裁定，如果在其实施过程中未能达成令人满意的补偿，原申诉方可以向争端解决机构申请授权报复。下列说法错误的是：

A．交叉报复措施是临时性的

B．交叉报复的领域包括货物贸易、服务贸易以及与贸易有关的知识产权领域

C．交叉报复的方式是对被诉方中止减让或中止其他义务，如果有关成员对减让水平提出异议，则应当由原专家组或总干事指定的仲裁员进行仲裁

D．仲裁裁定的事项包括审查被中止履行的减让和其他义务的性质，并且在仲裁期间，不得中止履行减让或其他义务