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: Which of these can be mined from Earth and used as an energy source? Answer: Coal

Answer: Coal can be mined from earth and used as an energy source.


Question: Question: What is the smallest unit of time commonly based on? Answer: second

Answer: Second is the smallest unit of time commonly based on.


Question: Question: In living systems, diffusion of substances into and out of cells is mediated by the what? Answer: plasma membrane

Answer:
In living systems, diffusion of substances into and out of cells is mediated by the plasma membrane.