1. A pump operating at 2000 lbf/in² and delivering 5 gal/min requires 7 bhp to drive the input shaft. Compute the overall efficiency of the pump. 2. A piston pump operating at 1200 rpm and 3000 lbf/in.² delivers fluid at 10 gal/min. If the pump has an overall efficiency of 95%. What is the input torque from the driving unit? 3. What is the volumetric efficiency of a pump with a displacement of 2.2 in³/rev that delivers 15 gal/min at 1725 rpm? 4. A hydraulic cylinder with a 2.5-in. bore and a 1.25-in. cylinder rod receives fluid at 12 gal/min through 3/4-in. Schedule 40 pipe. What is the velocity of the fluid through the return line when the cylinder is retracting? (Clue: draw an illustration showing the direction of flow.) 5. A 10-kN car and 5-kN hoist are supported 1.8 m above the floor by a cylinder with a 300- mm bore. What pressure will this develop in the system? 6. A 3-in. bore cylinder operating at 2000 lbf/in.2 is driving a load of 3000 lbf horizontally at 20 ft/min. Compute the force necessary to decelerate the load within a distance of 2 in. if the coefficient of friction is 0.15.