11A manhole is provided in sewers for:AAeration of soilBInspection and cleaningCRain collection onlyDWater supplyView AnswerDiscussWorkspaceReportSaveEasy
12A combined sewer carries:ABoth sewage and storm waterBOnly sewageCOnly storm waterDOnly industrial wasteView AnswerDiscussWorkspaceReportSaveEasy
13Grit chambers remove:ABacteriaBSand, gravel and heavy inorganic particlesCDissolved organicsDOils onlyView AnswerDiscussWorkspaceReportSaveEasy
14Self-purification of streams involves:AFreezingBDilution, sedimentation, oxidation and aerationCEvaporation onlyDAdding chlorine onlyView AnswerDiscussWorkspaceReportSaveEasy
15The activated sludge process is a:APhysical screeningBDisinfectionCBiological (secondary) treatmentDPrimary treatmentView AnswerDiscussWorkspaceReportSaveEasy