Q. If the depletion of oxygen is found to be 2.5 mg/litre after incubating 2.5 ml of sewage diluted to 250 ml for 5 days at 20°C, B.O.D. of the sewage is

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Q. The clarigesters are

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Q. Rate of flow of sewage is generally assumed

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Q. Maximum permissible velocity 1.5 m/sec, is adopted in drains

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Q. For design purposes, the normal rate of infiltration of ground water into the sewer, is

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Q. The effluent of a septic tank is

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Q. The drainage area of a town is 12 hectares. Its 40% area is hard pavement (K = 0.85), the 40% area is unpaved streets (K = 0.20) and the remaining is wooded areas (K = 0.15). Assuming the time of concentration for the areas as 30 minutes and using the formula Ps = 900/t+60 the maximum run off is

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Q. The detention period for plain sedimentation water tanks, is usually

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Q. To prevent settling down of sewage both at the bottom and on the sides of a large sewer, self-cleaning velocity recommended for Indian conditions, is

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Q. Pick up the correct statement from the following :

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Q. In sewers the gas generally found, is

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Q. A sewer running partially full and hurried with back filled, fails in compression due to

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Q. A manhole is classified as shallow if its depth is between

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Q. The ratio of the diameter of a circular section and the side of a square section hydraulically equivalent, is

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Q. Pick up the correct statement from the following :

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Q. For trunk and out-fall, the type of sewers generally used, is

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Q. Pick up the incorrect statement from the following :

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Q. Hydraulic mean radius is

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Q. Sewer ventilating columns are generally placed at

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Q. In case of Imhoff tanks,

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