Which of the following statements is correct with regards to the operation of a centrifuga

Which of the following statements is correct with regards to the operation of a centrifugal cargo pump？

A.Oil is discharged from the impeller through the outlet

B.Gravity causes the oil to flow toward the discharge

C.The self-priming feature of the centrifugal pump enables it to draw its own suction as it starts

D.The discharge capacity varies directly with the speed of the impeller

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