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Bacteria have flourished on the earth for over three billion years. They were the first life forms on the planet.
The average adult has about 21 square feet of skin.
Human stomach acid is strong enough to dissolve small pieces of metal such as razor blades or staples.
This year, an estimated 1.4 million Americans will have a new or recurrent heart attack.
Bacteria have been found alive in a lake buried one half mile under ice in Antarctica.
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