Life on the earth appeared around how many years before the present?
A. 13.7 billion
B. 4.6 billion
C. 3.8 million
D. 3.8 billion
Answer:D
Life on the earth appeared around how many years before the present?
A. 13.7 billion B. 4.6 billion C. 3.8 million D. 3.8 billion