218. Open channels supported over tresles, are generally known as
A. raised canals
B. acqueducts
C. syphons
D. flumes.

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219.  A pressure conduit carrying water beneath a stream or a canal, is known as
A. sag
B. depressed pipe
C. inverted syphon
D. all the above.

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220.  Pipes are laid parallel
A. to increase the capacity of the water supply
B. to provide a means of repairing without closing water supply
C. to meet the requirement of excessive supply
D. all the above.

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221. The maximum pressure to which a pipe is subjected to during its operation, is known
A. working pressure
B. design pressure
C. test pressure
D. pipe pressure

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222.  Cast iron pipes are generally preferred to, because
A. of moderate cost
B. of ease to join
C. of durability
D. all the above.

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223. . Air valves are generally provided in pressure pipes of water supply
A. at pipe junctions
B. at summits
C. at low points
D. near service pipes.

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224.  The valve fitted closely in a recess against an opening in a pipe, is generally
A. wedge shaped circular disc
B. spherical disc
C. parallelopiped disc
D. conical shaped circular disc.

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