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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."
Signs and symptoms that may signify an eye tumor include general blurred vision, bulging eye(s), double vision, a sensation of a foreign body in the eye(s), iris defects, limited ability to move the eyelid(s), limited ability to move the eye(s), pain or discomfort in or around the eyes or eyelids, red or pink eyes, white or cloud spots on the eye(s), colored spots on the eyelid(s), swelling around the eyes, swollen eyelid(s), and general vision loss.
Walt Disney helped combat malaria by making an animated film in 1943 called The Winged Scourge. This short film starred the seven dwarfs and taught children that mosquitos transmit malaria, which is a very bad disease. It advocated the killing of mosquitos to stop the disease.
Adult head lice are gray, about ? inch long, and often have a tiny dot on their backs. A female can lay between 50 and 150 eggs within the several weeks that she is alive. They feed on human blood.
Vaccines cause herd immunity. If the majority of people in a community have been vaccinated against a disease, an unvaccinated person is less likely to get the disease since others are less likely to become sick from it and spread the disease.