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• Granitic rocks from Rainy Lake are dated at between 2.75 and 2.72 billion years.
• These tools are usually reckoned to be between 10,000 and 11,000 years old.
Русско-английский научно-технический словарь• Granitic rocks from Rainy Lake are dated at between 2.75 and 2.72 billion years.
• These tools are usually reckoned to be between 10,000 and 11,000 years old.
Русско-английский научно-технический словарь