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问题 问答题

20℃时，氯化钠的溶解度为36g．在此温度下将30g氯化钠放入50克水中充分溶解．

（1）所得溶液溶质的质量分数是多少？

（2）若将该溶液配制成16%的氯化钠溶液用于农业选种，需要加水（或增加溶质）多少克？

答案

（1）20℃时，氯化钠的溶解度为36g，其涵义是20℃时，100g水中最多溶解36g氯化钠，溶液达到饱和状态，则将30g氯化钠放入50克水中充分溶解，最多只能溶解18g，所得溶液溶质的质量分数是

18g
18g+50g
×100%≈26.5%．

（2）设要加水的质量为x，根据溶液稀释前后，溶质的质量不变，

则（68g+x）×16%=18g    x=44.5g．

故答案为：（1）26.5%；（2）44.5g．

完形填空
完形填空。
     Sam is a bus driver in a big city.  All day he drives a bus through busy streets.Driving a big bus in very
   1    work.  It makes the drivers unhappy.  But not Sam!
     Sam is always happy.  And the people who ridc in his bus seem to be happy, too. This story shows 
  2  .
     Early one morning, Sam started his big green and yellow bus.  He went off on 3     work.  "Oh, what a beautiful morning!" he sang.   "Oh, what a beautiful day!"
     At the first bus stop, a man was     4    .  "Good morning, Mr. James," said Sam with a big smile. "How are you?"  ,
     "Fine, thank you. Sam," said Mr. James. "How are you?"
     "Wonderful!" Sam answered.  "Just wonderful! This is a fine day. "
     Mr. James smiled.  He took a seat.  As he looked   5   the window, he still smiled.
     At 6         stop a man came running up.  He was puffing (气喘吁吁 ).  "I have to-puff-catch a train at seven," he said.  "Can you-puff-get me to the station?"
     "Now, just sit down and rest," said Sam.  "I'll drive a little   7 .  We will be there in time.  Then you   8   run again."
     "Thank you. " said the man.  He sat down.
     Sam did drive! just a little faster.  He got to the station before seven!
    "Thank you," said the man, as he got off the bus.  "You are the best bus driver in the city ! "
     As he drove on, Sam       9     talking again. By this time, many people were on the bus.  They were all going to work.  But Sam made the ride seem like fun.
     "It is now ten minutes after seven," Sam called out.
     "The sky is blue.  It will not rain today.  We all like sunshine,  don't we?"
     He began to sing,  "I love you,  Mr.  Sunshine.  I love you,  Mr.  Sun.  In all the world I love you best.
You are the only one. "
     "What is that song, Sam?" a girl asked.
     "It's my song," he said.  "I made it up.  I like to sing.  It makes    10   people want to sing,  too."
     Sam was right! The man behind him started to sing!
( )1  A. easy      
( )2. A. what      
( )3. A. today's  
( )4. A. waiting  
( )5. A. into      
( )6. A. the first
( )7. A. faster    
( )8. A. don't    
( )9. A. liked    
( )10.A. another   		B.great        
B.why          
B.day's        
B.talking      
B.out of      
B.the last    
B.slower      
B.won't        
B.started      
B.the others   		C.interesting  
C.when          
C.the day's    
C.laughing      
C.at            
C.the other    
C.quicker      
C.won't have to
C.enjoyed      
C.others        		D.hard      
D.who        
D.the days  
D.riding    
D.up        
D.the next  
D.farther    
D.have to    
D.finished  
D.other      
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单项选择题

20×2年A公司发生了下列事项

（1）A公司销售给B公司一批货物，A公司按合同约定按期交货，B公司签发一张金额为20万元的转账支票交给A公司。A公司到银行提示付款时，发现该支票是张空头支票。A公司主张：中国人民银行应对B公司处以罚款，并要求B公司给予经济赔偿。

（2）A公司向B公司购买一批产品.向其交付了一张30万元的银行汇票，该汇票的收款人为B公司，付款人为C银行。因受市场变化的影响，该经济业务的实际结算金额变为35万元。B公司接受此银行汇票后，到C银行提示付款时，C银行拒绝付款。

（3）A公司某采购人员持有该公司开户银行签发的、不能用于支取现金的银行本票，前往甲公司购置一批价值10万元的产品。由于该采购人员保管不善，在途中将该银行本票丢失。随后，A公司根据该采购人员的报告，将银行本票遗失情况通知公司开户银行，要求挂失止付，但公司开户银行对上述情况进行审查后拒绝办理挂失止付。

（4）A公司和乙公司签订一项购销合同，A公司向乙公司开出出票后1个月付款的银行汇票。乙公司将汇票背书后向D公司转让，D公司又背书后向E公司转让。

（5）A公司2月从现金收入中直接支取5万元用于职工福利。

要求：根据上述资料，回答下列问题。

B公司应被中国人民银行处以（）元的罚款，给予A公司经济赔偿（）元。

A.10000；4000

B.4000；10000

C.10000；10000

D.4000；4000
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