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Bacteria have flourished on the earth for over three billion years. They were the first life forms on the planet.
Cyanide works by making the human body unable to use oxygen.
The familiar sounds of your heart are made by the heart's valves as they open and close.
About 3% of all pregnant women will give birth to twins, which is an increase in rate of nearly 60% since the early 1980s.
Fewer than 10% of babies are born on their exact due dates, 50% are born within 1 week of the due date, and 90% are born within 2 weeks of the date.
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