Q1: The quantity of liquid waste which flows in sewers during the period of rainfall, is known

ANS:C - storm sewage

The quantity of liquid waste that flows in sewers during the period of rainfall is known as storm sewage. Storm sewage refers to the runoff from rainfall events that enters the sewer system and is transported through the sewers to a treatment facility or discharged directly into water bodies. This runoff can include water from streets, rooftops, sidewalks, and other surfaces that collect rainwater during precipitation events. Unlike sanitary sewage, which consists of wastewater from domestic, commercial, and industrial sources, storm sewage primarily consists of rainwater and surface runoff. It may contain pollutants such as sediment, debris, oil, and other contaminants washed off from urban areas. Industrial waste, on the other hand, refers specifically to liquid or solid waste generated by industrial processes and discharged into the sewer system. While industrial waste may contribute to the overall flow in sewers, it is not specifically associated with rainfall events. Therefore, the correct term for the quantity of liquid waste that flows in sewers during the period of rainfall is storm sewage.