Q. How much percent of impurities are enough to make domestic sewage unfit for humans? 0.1 percent1 percent5 percent10 percent Answer: 0.1 percent

Q. Which of the following are the dissolved materials present in domestic sewage? SandClayNutrientsBacteria Answer: Nutrients

Q. Which of the following are the colloidal materials present in domestic sewage? CalciumSandAmmoniaFecal matter Answer: Fecal matter

Q. Which of the following are the suspended solids in the domestic sewage? AmmoniaSandCalciumBacteria Answer: Sand

Q. When the government of India did pass the Water (Prevention and Control of Pollution) Act? 1999197418962010 Answer: 1974

Q. Which of the following metal is a water pollutant and causes sterility in human being? AsMnMgHg Answer: Mn

Q. Which regions of seas/oceans are the most polluted ? EstuarineCoastalSea depthsCoral reefs Answer: Coastal

Q. Which of the following does not occur when the sewage is discharged into water? Increase in O2Cyanophycean blooms occurDepletion of O2 layersEutrophication Answer: Increase in O2

Q. Fishes die by sewage because Of its bad smellIt replaces food material of fishesIt increases oxygen competition among fishesCO2 is mixed in large amount in water Answer: Of its bad smell

Q. Foul smell in the water of tanks, ponds etc. is due to AnaerobiosisAerobiosisBiological magnificationPsammophytes Answer: Anaerobiosis

Q. Minamata disease is a pollution related disease results from Oil spills into seaAccumulation of arsenic into atmosphereRelease of industrial waste mercury into fishing waterRelease human organic waste into drinking water Answer: Release of industrial waste mercury into fishing water

Q. The excessive discharge of fertilizers into water bodies results in Growth of fishDeath of hydrophytesEutrophicationSilt Answer: Eutrophication