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Bacteria have flourished on the earth for over three billion years. They were the first life forms on the planet.
On average, someone in the United States has a stroke about every 40 seconds. This is about 795,000 people per year.
For about 100 years, scientists thought that peptic ulcers were caused by stress, spicy food, and alcohol. Later, researchers added stomach acid to the list of causes and began treating ulcers with antacids. Now it is known that peptic ulcers are predominantly caused by Helicobacter pylori, a spiral-shaped bacterium that normally exist in the stomach.
About 100 new prescription or over-the-counter drugs come into the U.S. market every year.
The Babylonians wrote numbers in a system that used 60 as the base value rather than the number 10. They did not have a symbol for "zero."