Carbon dating is a system of calculating the age of a very old object by measuring the amount of radioactive carbon it contains.
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Carbon dating is a system of calculating the age of a very old object by measuring the amount of radioactive carbon it contains.
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Collins COBUILD Advanced Learner's English Dictionary. Английский словарь Коллинз COBUILD для изучающих язык на продвинутом уровне. 2006