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问题 选择题

下列说法中不正确的是（NA代表阿伏加德罗常数的值）

A．13C与14C属于同一种元素，它们互为同位素

B．28g乙烯和氮气的混合气体中含有NA个气体分子

C．海轮外壳上镶入锌块，可减缓船体的腐蚀

D．常温下，1mol·L-1的 Na2CO3溶液中阴离子总数大于2NA

答案

答案：D

D项中溶液体积不确定，但所含粒子无法确定，答案为D

完形填空
完形填空。
     What about your future? There are four students who are talking   1   their future.    
     Han Ming: I want to be a pilot when I grow up. So I need good eyesight(视力) and I have to take
   2   lessons. I really   3   traveling.    
     Chen Ying: I want to be   4  engineer when I grow up.  I'm going to study design and engineering at
university. My   5   is to build the longest bridge in the world.
     Gao Liang: I want to be an actor when I grow up. I'm going to take acting lessons, and     6   singing
and dancing lessons, too.  I hope I can be   7   one day.      
     Zhang Wei: I want to be a    8   player when I grow up. I know that I have to train hard every day.  It isn't    9   , but I will keep on    10   it. I want to be just like my hero, Yao Ming, in the future.
( )1. A. with      
( )2. A. flying    
( )3. A. want      
( )4. A. an        
( )5. A. job      
( )6. A. may      
( )7. A. afraid    
( )8. A. basketball
( )9. A. difficult
( )10.A. did      

B. about      
B. swimming  
B. ask        
B. the        
B. subject    
B. can        
B. famous    
B. tennis    
B. different  
B. to do      

C. in        
C. singing  
C. make      
C. a        
C. dream    
C. maybe    
C. nervous  
C. badminton
C. easy      
C. do        

D. to      
D. playing  
D. enjoy    
D. /        
D. answer  
D. must    
D. worried  
D. soccer  
D. excited  
D. doing    
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多项选择题

下列关于瓣膜病的描述哪些是正确的（）

A.心室舒张功能可以描述为心室的顺应性

B.某些瓣膜疾病对左室产生容量负荷，引起离心性肥厚

C.某些瓣膜疾病对左室产生压力负荷，引起向心性肥厚

D.收缩功能可以描述为舒张末压与容量的关系

E.某些瓣膜病可以造成冠状动脉的供血不足
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