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问题 单项选择题

有一个摆地摊的摊主，他拿出3个白球，3个黑球，放在一个袋子里，让人们摸球中奖。只需2元就可以从袋子里摸3个球，如果摸到的3个球都是白球，可得10元回扣，那么中奖的概率是多少如果一天有300人摸奖，摊主能骗走多少元（）

A．1/40，350

B．1/20，450

C．1/30，420

D．1/10，450

答案

参考答案：B

解析：

6个球当中摸3个球有种情况，即20种情况，而摸3个都是白球只是其中的一种情况，即摸中的概率为；300人摸奖摊主能骗去的钱为元，故选B。

完形填空
完形填空。

     In the USA, Mother's Day is a holiday on the    1    Sunday in May. On that day    2    give their mother
cards, presents and flowers. One of the best    3    to celebrate Mother's Day is    4    your mother a day off
(休息一天). Let her have a good rest    5    other members of the family do the housework.
      Many families begin Mother's Day    6    breakfast in bed. Usually dad and the children will let mom    7  
 more as they go into    8    and get ready for her favorite meal.    9    the food is cooked, they keep everything
nice on a plate. They don't forget    10    the bottle with only one flower on the plate. Then dad and children
carefully carry the plate to mom's bedroom.
      Many families take mom to her favorite restaurant for a meal. It is a good day to let your mom have a
rest and let her see what a wonderful family she has.

( )1. A. first     
( )2. A. father    
( )3. A. ways      
( )4. A. give      
( )5. A. after     
( )6. A. with      
( )7. A. to sleep  
( )8. A. the bedroom
( )9. A. Before    
( )10. A. put       		B. second         
B. student       
B. cards        
B. to give        
B. before        
B. to            
B. sleeping        
B. the dining room  
B. After        
B. to put       		C. third     
C. children  
C. children  
C. giving    
C. while                  
C. of        
C. slept  
C. the kitchen 
C. On        
C. putting 		D. two        
D. boys       
D. mothers     
D. gives   
D. on         
D. for     
D. sleep     
D. the classroom 
D. Ago        
D. puts     
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多项选择题

复合卡的操作要点是什么（）。

A.卡放置在复合卡读写器上至少保持2-3秒以上

B.卡放置在复合卡读写器上至少保持5秒以上

C.保证入口信息完整读入

D.确保入口信息和路径标识站信息完整读取
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