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 is it called when poles are in opposite positions? Answer: reversed polarity

Answer: Reversed polarity is it called when poles are in opposite positions.

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: What do many scientists think are the oldest eukaryotes? Answer: protists

Answer:
Many scientists think protists are the oldest eukaryotes.