The horizontal fraction bar was introduced by the Arabs.
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It is believed that the Incas used anesthesia. Evidence supports the theory that shamans chewed cocoa leaves and drilled holes into the heads of patients (letting evil spirits escape), spitting into the wounds they made. The mixture of cocaine, saliva, and resin numbed the site enough to allow hours of drilling.
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Hippocrates noted that blood separates into four differently colored liquids when removed from the body and examined: a pure red liquid mixed with white liquid material with a yellow-colored froth at the top and a black substance that settles underneath; he named these the four humors (for blood, phlegm, yellow bile, and black bile).
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Individuals are never “cured” of addictions. Instead, they learn how to manage their disease to lead healthy, balanced lives.
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The heart is located in the center of the chest, with part of it tipped slightly so that it taps against the left side of the chest.
