Which statement is true about the work done in lifting a box? Group of answer choices D. The energy of the lifter remains constant.

C. The energy of the box remains constant.

B. Energy is transferred to the lifter from the box.

A. Energy is transferred to the box from the lifter.

Work out sian speed for the first 30 minutes of her journey. give your answer in km/h.

Calculate the first and second velocities of the car with four washers attached to the pulley, using the formulas v1 = 0.25 m / t1 , and v2 = 0.25 m / (t2 – t1) where t1 and t2 are the average times the car took to reach the 0.25 and the 0.50 meter marks. record these velocities, to two decimal places, in table e.

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)