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.

Q: Question: The concentration of the hydrogen ion in a solution can be calculated when what is known? Answer: ph

A: The concentration of the hydrogen ion in a solution can be calculated when the ph is known.
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Q: Question: What is the term for the transfer of heat by a current? Answer: convection

A: Convection is the term for the transfer of heat by a current.
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Q: Question: Which of the following statements best describes how the four planets closest to the Sun are different from the next four planets in our solar system? Answer: The four closest planets are more dense.

A:
The four closest planets are more dense of the following statements best describes how the four planets closest to the sun are different from the next four planets in our solar system.
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