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 do you call a substance that cannot be broken down to other substances by chemical reactions.? Answer: an element

Answer: You call a substance that cannot be broken down to other substances by chemical reactions an element.


Question: Question: What is one problem with current methods of aluminum production? Answer: environmental contaminants

Answer: Environmental contaminants is one problem with current methods of aluminum production.


Question: Question: What is defined as the velocity of the object at a given moment? Answer: instantaneous velocity

Answer:
Instantaneous velocity is defined as the velocity of the object at a given moment.