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

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: There are three types of mechanical waves. They differ in how they travel through a medium. The three types are transverse, longitudinal, and surface waves. All three types are described in detail below. Answer: three

A: How many types of mechanical waves are there?
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Q: Passage: When plants and other organisms die, decomposers break down their remains. In the process, they release nitrogen in the form of ammonium ions. Nitrifying bacteria change the ammonium ions into nitrates. Some of the nitrates are used by plants. Some are changed back to nitrogen gas by denitrifying bacteria. Answer: decomposers

A:
Which members of the food chain break down remains of plants and other organisms when they die?
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