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Elderly adults are living longer, and causes of death are shifting. At the same time, autopsy rates are at or near their lowest in history.
Bacteria have been found alive in a lake buried one half mile under ice in Antarctica.
Bacteria have flourished on the earth for over three billion years. They were the first life forms on the planet.
The Romans did not use numerals to indicate fractions but instead used words to indicate parts of a whole.
Cyanide works by making the human body unable to use oxygen.
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