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问题 单项选择题 A1/A2型题

乙脑病毒是通过（）

A.蚊子传播

B.虱子传播

C.跳蚤传播

D.蜜蜂传播

E.苍蝇传播

答案

参考答案：A

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       My name is Bill. I’m   1   American boy. I’m twelve. I’m a student of a middle school. I’m
in Class 4, Grade 1.   2   44 students in our class.Li Lei is my friend. We are in the same class. He is
eleven. Here’s a picture of   3   family.   4   look at it. The policeman on the chair is his father. His
mother is a teacher of Chinese. These are his twin sisters. They have a cat.   5   name is Mimi. Look!
It’s   6   the floor under the table.   7   twins are middle school students, too. They are in the    8   class. How many   9   students are there in their class? There is only   10  .
( )1. A. the          
( )2. A. They        
( )3. A. his    
( )4. A. Let          
( )5. A. It's        
( )6. A. on          
( )7. A. And          
( )8. A. different    
( )9. A. China        
( )10. A. some        		B. an            
B. They're      
B. him          
B. Let's        
B. Its'        
B. in            
B. /            
B. same          
B. England      
B. any           		C. a                
C. There're        
C. he              
C. We              
C. Its              
C. behind          
C. The              
C. one              
C. American        
C. one              
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问答题

小明和小亮两名同学用下列甲、乙、丙三种装置，使用二氧化锰固体与过氧化氢溶液在常温下作用，制取氧气并实验氧气的性质．

（1）写出上面装置中a、b的仪器名称：a______b______；

（2）从上述实验装置中，你能得出氧气的性质有______；（答一条即可）

（3）写出过氧化氢分解制氧气的化学方程式______；在该反应中二氧化锰起______作用．

（4）气体发生装置中长颈漏斗下端在液面以下的原因是______．

（5）写出丙图中铁丝在氧气中燃烧的化学方程式______；小明用该图中的实验装置完成实验后，发现集气瓶炸裂，原因是______．
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