Environmental Engineering in CE The ratio of oxygen available to the oxygen required for stabilisation of sewage is called the Biological oxygen demand (BOD) Relative stability Oxygen ion concentration Bacterial stability factor Biological oxygen demand (BOD) Relative stability Oxygen ion concentration Bacterial stability factor ANSWER DOWNLOAD EXAMIANS APP
Environmental Engineering in CE Iron & manganese present in the polluted water is removed by Simple filtration Oxidation followed by settling & filtration Chemical coagulation Chlorination only Simple filtration Oxidation followed by settling & filtration Chemical coagulation Chlorination only ANSWER DOWNLOAD EXAMIANS APP
Environmental Engineering in CE Maximum allowable noise exposure limits for a man working for 8 hours a day in a noisy chemical plant is about __________ decibels. 120 60 20 90 120 60 20 90 ANSWER DOWNLOAD EXAMIANS APP
Environmental Engineering in CE Threshold Limit Value (TLV) is the maximum allowable concentration (i.e. safe limit) of pollutants in air. Safe limit for SO₂ in air is __________ ppm. 500 5 1000 2000 500 5 1000 2000 ANSWER DOWNLOAD EXAMIANS APP
Environmental Engineering in CE The lowest layer of atmosphere is known as the Stratosphere Ionosphere Troposphere None of these Stratosphere Ionosphere Troposphere None of these ANSWER DOWNLOAD EXAMIANS APP
Environmental Engineering in CE Coal mines drainage waste water (acidic in nature) results from the earth's water percolating through the voids created in coal bed during mining. This polluted water which either drains out naturally to water courses or are removed before starting the mining is Diluted with fresh water to reduce its acidity None of these Neutralised by alkali treatment Left as such without any treatment Diluted with fresh water to reduce its acidity None of these Neutralised by alkali treatment Left as such without any treatment ANSWER DOWNLOAD EXAMIANS APP
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