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Normal urine is sterile. It contains fluids, salts, and waste products. It is free of bacteria, viruses, and fungi.
Vaccines prevent between 2.5 and 4 million deaths every year.
Bacteria have flourished on the earth for over three billion years. They were the first life forms on the planet.
The ratio of hydrogen atoms to oxygen in water (H2O) is 2:1.
The Romans did not use numerals to indicate fractions but instead used words to indicate parts of a whole.
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