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The horizontal fraction bar was introduced by the Arabs.
Asthma is the most common chronic childhood disease in the world. Most children who develop asthma have symptoms before they are 5 years old.
Egg cells are about the size of a grain of sand. They are formed inside of a female's ovaries before she is even born.
Russia has the highest death rate from cardiovascular disease followed by the Ukraine, Romania, Hungary, and Poland.
The human body produces and destroys 15 million blood cells every second.
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