In 1844, Charles Goodyear obtained the first patent for a rubber condom.
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The ratio of hydrogen atoms to oxygen in water (H2O) is 2:1.
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Everyone has one nostril that is larger than the other.
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It is widely believed that giving a daily oral dose of aspirin to heart attack patients improves their chances of survival because the aspirin blocks the formation of new blood clots.
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Pregnant women usually experience a heightened sense of smell beginning late in the first trimester. Some experts call this the body's way of protecting a pregnant woman from foods that are unsafe for the fetus.
How to solve word problems with two unknowns (Question 4)