Given a scientific passage and an answer, generate a question for the given answer.

Q: Passage: Hydraulic car lifts also use fluid to transmit pressure and increase force. The lifts are used to raise cars, which are very heavy, so mechanics can work on them from underneath. Controls in airplanes use fluids to transmit pressure and increase force so a flick of a switch can raise or lower heavy landing gear. To see animations of hydraulic systems such as these, go to URLs:. Answer: hydraulic systems

A: What kind of systems use fluid to transmit pressure and increase force?
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Q: Passage: The energy in sunlight, or solar energy, can be used to heat homes. It can also be used to produce electricity in solar cells. However, solar energy may not be practical in areas that are often cloudy. Answer: solar energy

A: The energy in sunlight is also known as what kind of energy?
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Q: Passage: Sources of voltage include electric generators and cells. Electric generators change kinetic energy to electrical energy. Chemical cells change chemical energy to electrical energy, and solar cells change solar energy to electrical energy. Answer: electrical

A:
Electric generators change kinetic energy to what type of energy?
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