In this task, you are given a question and an answer, you would be asked to create the sentence based on the Question-Answer provided. It should be contained within the Question-Answer provided.
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Question: Question: What type of hydrocarbon is coal? Answer: solid

Answer: Solid type of hydrocarbon is coal.


Question: Question: Loss of energy is the reason that what typically has few levels? Answer: food chain

Answer: Loss of energy is the reason that food chain typically has few levels.


Question: Question: Objects in motion that return to the same position after a fixed period of time are said to be in what type of motion? Answer: harmonic

Answer:
Objects in motion that return to the same position after a fixed period of time are said to be in harmonic type of motion.