By 10,000 years ago, about ________ people inhabited the entire world; today there are over ________.

A. 350,000; 300 million
B. 65 million; 9 billion
C. 5 million; 6 billion
D. 500,000; 1 billion
E. 1 million; 20 billion


Answer: C

Biology & Microbiology

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Biology & Microbiology