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问题 单项选择题

二尖瓣狭窄最常见的心律失常是（）。

A.室性心律失常

B.房室传导阻滞

C.心房颤动

D.窦性心动过缓

E.阵发性室上性心动过速

答案

参考答案：C

完形填空
完型填空。
      There is good news for the children in the countryside. We may still remember the girl   1   big eyes. Her big
eyes are   2   us her dream: I wish to   3  ! In China, there are still   4   girls and boys like her. They want to go
to school, but their   5   are too poor. If the family has two or three children, it is harder to   6   the money for all
the children. So the parents often ask   7   to stay at home, and boys to go to school. 
      Now they needn't   8   the money. From 2006 on, children can go to school for free in some poor places.
They don't have to pay for books and other things. Some of them can even get money from the government to
make their life   9  . Soon, all the children in the countryside can go to school for free. All families are very happy
with the news. It is   10   great.
( ) 1. A. with      
( ) 2. A. saying    
( ) 3. A. go to work 
( ) 4. A. a lot     
( ) 5. A. schools   
( ) 6. A. pay       
( ) 7. A. teachers  
( ) 8. A. look up   
( ) 9. A. better    
( ) 10. A. not        		B. on       
B. telling    
B. go to bed        
B. lot of     
B. cities   
B. take       
B. girls      
B. turn on  
B. shorter  
B. never     		C. to            
C. speaking      
C. go to school    
C. a lot of      
C. houses        
C. buy           
C. boys          
C. worry about   
C. longer        
C. hardly       		D. in              
D. talking           
D. go home              
D. much              
D. families          
D. lend            
D. all the children  
D. make sure         
D. worse             
D. really          
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问答题

(1)将函数f(x)=x-1(0≤x≤2)展开成周期为4的余弦级数；
(2)求
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