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Author Question: Describe the set of points in 3-space defined by the equations x2 + y2 + z2 - 8z = 9, x = 3. (Read 33 times) |
People who have myopia, or nearsightedness, are not able to see objects at a distance but only up close. It occurs when the cornea is either curved too steeply, the eye is too long, or both. This condition is progressive and worsens with time. More than 100 million people in the United States are nearsighted, but only 20% of those are born with the condition. Diet, eye exercise, drug therapy, and corrective lenses can all help manage nearsightedness.
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).
Side effects from substance abuse include nausea, dehydration, reduced productivitiy, and dependence. Though these effects usually worsen over time, the constant need for the substance often overcomes rational thinking.
In most climates, 8 to 10 glasses of water per day is recommended for adults. The best indicator for adequate fluid intake is frequent, clear urination.
Approximately 15–25% of recognized pregnancies end in miscarriage. However, many miscarriages often occur before a woman even knows she is pregnant.