Electric bills According to the US Energy Information Admini

Electric bills: According to the U.S. Energy Information Administration, the mean monthly household in the United States in 2007 was $99.70. Assume the amounts are normally distributed with standard $2000. a. What proportion of balls are greater than $130? What proportion of bills are between $85 and $140? What is the probability that a randomly selected household had a monthly bill less than $110?

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