[PDF] Cambridge International AS & A Level 19 A water pump is driven by an engine. The pump raises a volume of 0 m3 of water in 1.0 minute from a depth of 30 m. The pump has an efficiency of 70%. The density of water is 1000 kg m –3. What is the useful output power from the engine? A 2.5 kW B 3.5 kW C 150 kW D 210 kW Car Maintenance, Repairs, & How-Tos - LiveAbout Car Maintenance, Repairs, & How-Tos. It's both useful and empowering to know how to fix your own car. Whether you need to test the condition of your car battery, fix your AC, or simply change your tires, learn how with these step-by-step tutorials.