51. Mathamoglobinemia, or blue baby disease is caused due to
52. The main process to purify water by filtration, is
53. Surface water is obtained from
54. Hardness of water is caused due to
55. Flow through period, in sedimentation tanks, is
56. Normal values of overflow rate for plain sedimentation tank, is
57. Who was the first vice president of America?
58. The force which develops in a pressure conduit supported on trestles, is
59. After cleaning a slow sand filter, the filtered water is not used for
60. A pressure conduit laid under ground, may not be subjected to
61. The period of cleaning of a slow sand filter, is usually
62. At the socket and spigot joint,
63. Gravity conduits for carrying water from the source are
64. Continuous flow of water can be expected from
65. The maximum hourly consumption, is generally taken as
66. A city supply includes
67. During treatment of water, sedimentation is done
68. E. Coli bacterias die in water having pH greater than
69. Check valves are installed
70. Fear of pain is?
71. If intensity of rainfall in cm per hour is I, percentage coefficient of run-off is P, area of catchment in square kilometres is A, the total run-off Q, is given by
72. Hard water contains
73. The main disadvantage of hard water, is
74. An area is declared drought affected if its mean rainfall is less than
75. The best quality of filter material is obtained from quartzite if it does not loose weight when placed in hydro-chloric acid for 24 hours, more than