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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.
More than 4.4billion prescriptions were dispensed within the United States in 2016.
The heart is located in the center of the chest, with part of it tipped slightly so that it taps against the left side of the chest.
The horizontal fraction bar was introduced by the Arabs.
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