End of Section Problem 9.6 The Environmental Protection Agency releases figures on urban air soot in selected cities in the United States. For the...

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End of Section Problem 9.6 The Environmental Protection Agency releases figures on urban air soot in selected cities in the United States. For the city of St. Louis, the EPA claims that the averagenumber of micrograms of suspended particles per cubic meter of air is 82. Suppose St. Louis officials have been working with businesses, commuters, and industries toreduce this figure. These city officials hire an environmental company to take random measures ofair soot over a period of several weeks. The resulting data follow.Assume that the population standard deviation is 9.184. Use these data to determine whether the urban air soot in St. Louis is significantly lower than it was when theEPA conducted its measurements. Let a = .01. If the null hypothesis is rejected, discuss the substantive hypothesis. 81.6 66.6 70.9 82.5 58.3 71.6 72.496.6 78.6 76.1 80.0 73.2 85.5 73.268.6 74.0 68.7 83.0 86.9 94.9 75.677.3 86.6 71.7 88.5 87.0 72.5 83.085.8 74.9 61.7 92.2 (Round your answer to 2 decimal places.) The value of the test statistic is z = and we l—B. Click if you would like to Show Work for this question: Qpen Show Work