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Check My Work (3 remaining) A simple random sample of 30 items resulted in a sample mean of 70. The population standard deviation is o = 15. a. Compute the 95% confidence interval for the population mean. Round your answers to one decimal place. b. Assume that the same sample mean was obtained from a sample of 110 items. Provide a 95% confidence interval for the population mean. Round your answers to two decimal places. c. What is the effect of a larger sample size on the interval estimate? Larger sample provides a - Select your answer - v margin of error