Ordering of Sentences
                    
                    
                                                            S1: Machines have parts made of iron. P: They must be painted or chrome plated. Q: Some parts rub against each other. R: Iron gets rusted. S: They must be lubricated with oil or grease. S6: When the machine is not in use, it should be covered. The Proper sequence should be:
                                    
                
                
            
            
            
            
                                                
                        
            
            
                        
            
                
                
                
            
                        
                        
            
            
                        
            
                
                
                
            
                        
                        
            
            
                        
            
                
                
                
            
                        
                        
            
            
                        
            
                
                
                
            
                        
                        
            
            
                        
            
                
                
                
            
                        
                     
        
     
            
            
            
         
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