direction or the other. The normal curve is not skewed. It’s got a nice hump (only one), and that hump is right in the middle. Second, the normal curve is perfectly symmetrical about the mean. If you fold one half of the curve along its center line, the two halves would lie perfectly on top of each other. They are identical. One half of the curve is a mirror image of the other. Finally (and get ready for a mouthful), the tails of the normal curve are asymptotic—a big word. What it means is that they come closer and closer to the horizontal axis but never touch. See if you have some idea (in
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