Two… one to tell the engineer to do it, the other to say "I don't know, what do you think?" 
  
               
   
            
            
			
       
           
       
           
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            Because the chicken was on vacation.
  
               
   
            
            
			
       
           
       
           
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            Three. One to climb the ladder while the second kicks the ladder out from under her. And the third to say, "I knew that was too high for you dear."
  
               
   
            
            
			
       
           
       
           
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            Because it might crack up!
  
               
   
            
            
			
       
           
       
           
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            Just one, but he/she will spend hours checking for technical problems.
  
               
   
            
            
			
       
           
       
           
            or