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3r 1. At a local university, a sample of 49 evening students was selected in order to determine whether the average score of the evening students is significantly different from 85. The average score of the students in the sample was 84.2. The population standard deviation is known to be 2. a. Determine whether or not the evening students' average score is significantly different from 85. Use u=.05. b. Would your answer be different if d=.005? Please explain. c. Construct a 95% confidence interval for the population mean. 2. A store takes a random sample of 25 sales. The average price for this sample is $310 with a standard deviation of $48. Assume that sales are distributed normally. a. Please test the hypothesis when the sample mean is different from $300. b. Please test the hypothesis when the sample mean is greater than $300. c. Construct a 95% confidence interval for the population mean