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The ratio of hydrogen atoms to oxygen in water (H2O) is 2:1.
Blood in the urine can be a sign of a kidney stone, glomerulonephritis, or other kidney problems.
After a vasectomy, it takes about 12 ejaculations to clear out sperm that were already beyond the blocked area.
Vaccines prevent between 2.5 and 4 million deaths every year.
If all the neurons in the human body were lined up, they would stretch more than 600 miles.
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