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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).
In the United States, there is a birth every 8 seconds, according to the U.S. Census Bureau's Population Clock.
Looking at the sun may not only cause headache and distort your vision temporarily, but it can also cause permanent eye damage. Any exposure to sunlight adds to the cumulative effects of ultraviolet (UV) radiation on your eyes. UV exposure has been linked to eye disorders such as macular degeneration, solar retinitis, and corneal dystrophies.
Glaucoma is a leading cause of blindness. As of yet, there is no cure. Everyone is at risk, and there may be no warning signs. It is six to eight times more common in African Americans than in whites. The best and most effective way to detect glaucoma is to receive a dilated eye examination.
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."

