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问题 选择题

二次函数y=-3（x+2）2+1的图象顶点坐标是（　　）

A．（-2，-1）

B．（-2，1）

C．（2，1）

D．（2，-1）

答案

根据题意可得：顶点坐标是（-2，1）．

故选B．

单项选择题

患者，男，39岁，因大面积银汞合金充填要求冠修复。查：大面积银汞补，补物完好，不松动。X线牙片显示：根管治疗良好。拟为该患者行铸造全冠修复

铸造全冠颈部肩台宽度通常为（）

A．无肩台

B．0.5～0.8mm

C．0.8～1.5mm

D．1.5～2.0mm

E．25mm
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完形填空
完形填空。

     Water costs money．In some places water is hard__1__．What__2__when a town has
these problems？A small town in California found a happy__3__．
     Very__4__rain ever fell there．The town had no water__5__．The water it used was
 __6__from a river 300 miles away．As more people__7__live in the town,__8__water
was needed．Now water __9__to be brought in from 600 miles away．All these cost  
__10__money．
     The town__11__a plan．It found__12__ to clean its “dirty” water．Once the cleaned
water was reused__13__many ways．Five__14__lakes were built．Here people could
swim and fish and go__15__ ．They __16__have picnics in their new parks．Farmers had
more water __17__their crops．New factories can be built，now that they have the promise
of __18__．
     In most places，water is used and thrown__19__．The town that saved__20__water
has saved the town！

( )1.A．supplying     
( )2.A．happens         
( )3.A．key            
( )4.A．little          
( )5.A．of itself       
( )6.A．fetch          
( )7.A．come to      
(    )8.A．many          
( )9.A．has          
( )10.A．many          
( )11.A．put          
( )12.A．a way         
( )13.A．for          
( )14.A．man-making     
( )15.A．boating     
( )16.A．must           
( )17.A．as        
( )18.A．water enough   
( )19.A．off          
( )20.A．it’s       

B．getting       
B．happening        
B．answer         
B．a little        
B．of its own      
B．take             
B．came to         
B．plenty  of        
B．had            
B．a few           
B．made             
B．ways          
B．by               
B．man-make         
B．to boat          
B．could           
B．with             
B．enough water    
B．of              
B．its          

C．to get               
C is happened          
C answering          
C．few              
C．for its own       
C．brought in          
C．coming to           
C．more               
C．must               
C．a great many        
C．supply              
C．an answer           
C．at                   
C．man-made         
C．to boating       
C．needed              
C．for                    
C. crops enough       
C．away                
C．one’s          		D．to supply            
D．happened             
D．way                   
D．a few                
D for itself            
D．guided              
D．came for              
D．many more           
D．needed               
D．a lot of           
D．noticed            
D．a key                 
D．in                
D．man made             
D．on boating           
D．had to                 
D．to                     
D．enough crops       
D．out of                 
D．his            
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