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Answer:
The concentration of a substance is the quantity of solute present in a given quantity of solution.
How old is Darren? we need to know his age before we answer
Answer:
A mutation is a change that occurs in our DNA sequence, either due to mistakes when the DNA is copied or as the result of environmental factors such as UV light and cigarette smoke. Mutations can occur during DNA replication if errors are made and not corrected in time.