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问题 单项选择题

某电力用户设35/10kV变电站，10kV系统为中性点不接地系统，下设有三个10kV车间变电所，其中主要是二级负荷。其供电系统图和已知条件如下：

(1)35kV线路电源侧短路容量无限大。

(2)35/10kV变电站为重要变电所。

(3)35/10kV变电站10kV母线短路容量104MVA。

(4)A、B和C车间变电所10kV母线短路容量分别为102MVA、100MVA、39MVA。

(5)车间B变电所3号变压器额定电压10/0.4kV，其低压侧母线三相短路超瞬态电流为16330A。

(6)35/10kV变电站正常时间A、B和C车间变电所供电的三个10kV出线及负载的单相对地电容电流分别为2.9A、1.3A、0.7A，并假设各出线及负载的三相对地电容电流对称。

(7)保护继电器接线系数取1。

请回答下列问题：

如果向车间C供电的10kV线路发生单相接地故障，在该供电线路电源端装设无时限单相接地保护装置，计算其整定值应为下列哪项数值（）。

A．10A

B．15A

C．4.9A

D．2.1A

答案

参考答案：D

完形填空
完形填空。
     "Cheese"-a metaphor (隐喻) for what we want to have in life, whether it is a job, a relationship, or money. 
     Each of us has our own   1   of what cheese is, and we want to   2   it because we believe it makes us   3  .
     Once there lived four little characters. Two were   4   named Sniff and Scurry and two were little people
named Hem and Haw.
     Every morning, the mice and the little people   5   their running wear and went to Cheese Station C   6   they
found their cheese. It was such a large store of cheese that Hem and Haw   7   moved their homes to be closer
to it.
     One morning, Sniff and Scurry arrived at Cheese Station C and discovered there was   8   cheese. They
weren't surprised.   9   they had noticed the supply  10  cheese had been getting smaller every day, they were
prepared for the result. They set out quickly to  11  new cheese.
     Later that same day, Hem and Haw arrived. "What? No cheese! Who moved my cheese?" Hem yelled. They
went home that night  12  and discouraged.
     The next day Hem and Haw  13  to Cheese Station C. But the situation hadn't changed. Haw asked, "Do Sniff
and Scurry know something we don't know?" Hem  14  him and said, "What would they know? They are
simple  15  and we are human beings. They cannot be  16  than we are."
     Haw suggested, "Maybe we should  17  talking about the situation and just look for some new cheese."
     Haw decided to  18  Cheese Station C while Hem was more comfortable staying in the cheeseless Station C. 
     Meanwhile, Sniff and Scurry went farther  19  they found Cheese Station N. They found what they had been
looking for. It was the biggest  20  of cheese the mice had ever seen.
( )1. A. feeling    
( )2. A. get        
( )3. A. happy      
( )4. A. humans     
( )5. A. put in     
( )6. A. where      
( )7. A. firstly    
( )8. A. some       
( )9. A. For        
( )10. A. with      
( )11. A. search for
( )12. A. glad      
( )13. A. returned  
( )14. A. smiledat  
( )15. A. animals   
( )16. A. morefoolish
( )17. A. start     
( )18. A. leave     
( )19. A. if        
( )20. A. store      		B. idea         
B. avoid        
B. angry        
B. dogs         
B. took off     
B. that         
B. suddenly     
B. no           
B. If           
B. of           
B. find         
B. hopeful      
B. left         
B. laughed at   
B. cheese-lovers 
B. bigger       
B. stop         
B. go           
B. unless       
B. factory       		C. worry      
C. follow     
C. full       
C. mice       
C. gave in    
C. which      
C. finally    
C. any        
C. Though     
C. for        
C. look after 
C. unsatisfied
C. walked     
C. blamed     
C. thieves    
C. smarter    
C. get        
C. move       
C. when       
C. company     		D. hope            
D. try             
D. worried         
D. cats            
D. put on          
D. what            
D. always          
D. much            
D. Since           
D. to              
D. discover        
D. excited         
D. ran             
D. praised         
D. Sniff and Scurry        
D. faster          
D. enjoy           
D. start           
D. until           
D. home            
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选择题

在神经调节方面，人类区别于动物的特点是[ ]

A．人能对语言、文字的刺激发生反应

B．人的大脑皮层具有语言中枢

C．人能有目的进行社会性劳动和生活

D．以上三种特点都是
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