Is density independent of sample size?

How do we measure or think of speed in the united states?

You can watch static electricity in action by rubbing an inflated balloon against your hair. your hair will actually stand on its end! it does this because each hair becomes charged, and they all repel one another.

1) what is the power in horsepower of a 100 watt light bulb? what is the power in kilowatts of a 200 horsepower engine? 2) if a cars engine is providing 3000 n of force to keep the car moving at 5 m/s, what is the engine’s effective power? 3) how many gallons of water will be pumped from a well 30 feet deep by a 1/2 hp engine in 1 minute? (1 gallon weighs 8.34 pounds)