Ordering of Sentences
                    
                    
                                                            S1: The houses in the Indus Valley were built of baked bricks. P: This staircase sometimes continued upwards on to the roof. Q: Access to the upstairs rooms was by a narrow stone staircase at the back of the house. R: The drains were incorporated in the walls. S: The houses had bathrooms and water closets, rubbish chutes and excellent drainage systems. S6: They led outside into covered sewers which ran down the side of the streets. The Proper sequence should be:
                                    
                
                
            
            
            
            
                                                
                        
            
            
                        
            
                
                
                
            
                        
                        
            
            
                        
            
                
                
                
            
                        
                        
            
            
                        
            
                
                
                
            
                        
                        
            
            
                        
            
                
                
                
            
                        
                        
            
            
                        
            
                
                
                
            
                        
                     
        
     
            
            
            
         
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