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

Answer: The concentration of the hydrogen ion in a solution can be calculated when the ph is known.


Question: Question: In what way do all vertebrates reproduce? Answer: sexually

Answer: All vertebrates reproduce sexually.


Question: Question: Which of the following correctly lists the structures in space from smallest to largest? Answer: star, solar system, galaxy, universe

Answer:
Star, solar system, galaxy, universe of the following correctly lists the structures in space from smallest to largest.