In 1844, Charles Goodyear obtained the first patent for a rubber condom.
Did you know?
Approximately 70% of expectant mothers report experiencing some symptoms of morning sickness during the first trimester of pregnancy.
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During the twentieth century, a variant of the metric system was used in Russia and France in which the base unit of mass was the tonne. Instead of kilograms, this system used millitonnes (mt).
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Acetaminophen (Tylenol) in overdose can seriously damage the liver. It should never be taken by people who use alcohol heavily; it can result in severe liver damage and even a condition requiring a liver transplant.
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Most childhood vaccines are 90–99% effective in preventing disease. Side effects are rarely serious.
Map of the World's Religions
pie chart of the World's Religions
World Religions
African Religions
The World's Religions (4th Edition)
Transmission genetics began with the study of pea plants.
