A double-acting reciprocating pump with a crank radius of 25 cm and a piston diameter of 22 cm operates with an overall efficiency of 85%. If the power required to run the pump is 50 HP and the piston...

A double-acting reciprocating pump with a crank radius of 25 cm and a piston diameter of 22 cm operates with an overall efficiency of 85%. If the power required to run the pump is 50 HP and the piston rod diameter is 3 cm, what is the operating speed of the pump knowing that the static head is 7.5 m? Neglect the effect of water slip.