圆x2+y2+2x=0和x2+y2﹣4y=0的公共弦所在直线方程为( ) A.x

题型:选择题

问题:

圆x2+y2+2x=0和x2+y2﹣4y=0的公共弦所在直线方程为(  )

A.x﹣2y=0

B.x+2y=0

C.2x﹣y=0

D.2x+y=0

考点:点到直线的距离
题型:选择题

单词拼写

1.What's your______(态度)to solving the problem?

2. Your early reply will be highly ________(感激).

3. She was late and I  __________ (同样地) was delayed.

4. They heard the sound of a car ________(接近).

5. He lay on the ground,________(疲惫不堪).

题型:选择题

阅读理解。

     All students need to have good habits(习惯): When you have good study

habits, you learn things quickly. You also remember them easily.

     Do you like to study in the living room? This is not a good place because

it is usually too noisy. You need to study in a quiet place, like your bedroom. A quiet place will help you only think about one thing, and you will learn

better.

     Before you begin to study, do not forget to clean your desk. A good desk

light(台灯) is important, too. You’ll feel tired easily if there is not enough

light.

1. When you have good study habits, you will_____.

A. learn things quickly          

B. remember things easily

C. think about one thing        

D. both A and B

2. The living-room is not a good place for study because it is too _____.

A. quiet        

B. noisy      

C. good      

D. clean

3. You’ll feel tired easily if the light is _____.

A. good        

B. enough    

C. bad  

D. wonderful

4. You should remember to _____ before you study.

A. clean the desk              

B. tidy the room  

C. turn on the light             

D. go to the bedroom.

题型:选择题

已知某CO和02的混合气体中,碳元素、氧元素的质量比为1:4,现取12g该混合气体在密闭容器中点燃,充分反应后,生成二氧化碳的质量为

A.3.8g

B.8.8g

C.12g

D.13.2g.

题型:选择题

Captopril试验的目的是要提高哪种疾病的检出灵敏度和特异性()。

A.肾性高血压

B.输尿管痉挛

C.肾功能受损

D.急性肾盂肾炎

E.尿路梗阻

题型:选择题

机动车达到国家规定的强制报废标准的不能办理注册登记。

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