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A sample of size n = 81 is drawn from a population whose standard deviation is o = 5. Part 1 of 2 (a) Find the margin of error for a 90% confidence interval for u. Round the answer to at least three decimal places. The margin of error for a 90% confidence interval for u is Part 2 of 2 (b) If the sample size were n = 44, would the margin of error be larger or smaller? ( Choose one) v, because the sample size is (Choose one) V