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问题 多项选择题

（）适用于描述较长时间段内的期货价格走势。

A.分时图

B.K线图

C.闪电图

D.竹线图

答案

参考答案：B, D

解析：表述期货价格走势的主要图示方法有：闪电图和分时图、K线图和竹线图。其中，闪电图和分时图通常在日内交易时使用；K线图和竹线图适用于较长时间段。

完形填空
完形填空。

     Sam had a dog. Its name was Tod. It was very helpful, but it ate too much. So he didn't like it, he wanted
to    1   it. He    2   Tod and put it in a small boat. He rowed the boat to the   3    of a big river. Just as he   4   
the poor animal into the river, the boat began to go down.    5   the man and Tod    6   into the river.
     Tod was able to swim,    7   Sam couldn't. The dog bit the rope (绳子) and broke (破坏) it. It tried its best
to swim to   8    Sam. The man was saved, so he was very thankful for the dog and he didn't want to kill the
dog    9  . From then on, he gave the dog as    10   as it wanted.

( )1. A. sell     
(     )2. A. tied     
(     )3. A. front    
(     )4. A. threw    
(     )5. A. Neither  
(     )6. A. fell     
(     )7. A. because  
(     )8. A. kill     
(     )9. A. no more  
(     )10. A. little    		B. buy       
B. pulled    
B. foot      
B. carried   
B. Nor       
B. swam           
B. though    
B. save      
B. any more  
B. few       		C. beat       
C. pushed     
C. side       
C. sent      
C. Each        
C. lost              
C. but         
C. meet        
C. no longer  
C. many      		D. kill
D. closed                      
D. middle                     
D. brought                    
D. Both                        
D. jumped                       
D. when                         
D. hit                          
D. not more                      
D. much                    
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解答题
已知M（a，b），N（sinωx，cosωx）（ω＞0），记f（x）=
OM
•
ON
（O为坐标原点）．若f（x）的最小正周期为2，并且当x=
1
3
时，f（x）的最大值为5．
（1）求函数f（x）的表达式；
（2）对任意的整数n，在区间（n，n+1）内是否存在曲线y=f（x）的对称轴？若存在，求出此对称轴方程；若不存在，说明理由．
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