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.
N-UNCOUNT
Collins COBUILD. Толковый словарь английского языка для изучающих язык Коллинз COBUILD (международная база данных языков Бирмингемского университета) . 2012