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: What is a winding ridge of sand deposited by a stream of meltwater called? Answer: esker

Answer: A(n) esker is a winding ridge of sand deposited by a stream of meltwater called.


Question: Question: The thick skin, found only on the palms of the hands and the soles of the feet, has an extra what? Answer: layer

Answer:
The thick skin, found only on the palms of the hands and the soles of the feet, has an extra layer.