A.apparent slip
B.tree slip
C.pitch
D.propulsive efficiency

A.two or more impellers housed together in one casing and mounted on a single shaft
B.a single stepped impeller mounted in a progressively staged casing
C.a large radial clearance between the impeller and casing to prevent overheating due to
D.an increase in the discharge velocity of the liquid with a corresponding decrease in pressure through the stages