Which of the following pumps are self-priming, and can deal with liquid from a level below the pump? () (1) reciprocating (2) rotary (3) centrifugal
A.(1)only B.(1)and (2) C.(1),(2)and(3) D.(2)and(3)
A.throttling the pressure line B.changing the speed of the driving rotor C.either A or B D.None of the above is tree
A.throttling the pressure line B.changing the speed of the piston C.either A or B D.None of the above is tree