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IQ is normally distributed with mean 100 and standard deviation 15. An IQ of 130 or...

IQ is normally distributed with mean 100 and standard deviation 15. An IQ of 130 or above is considered gifted, and 150 and above is considered genius. There are 350 million people living in the United States.

1. Let X be the IQ of a person randomly selected from the population. Compute Var(X^2). (Use binomial expansion!)

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