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Use the standard normal distribution or the t-distribution to construct a 99% confidence interval for the population mean. Justify your decision. If neither distribution can be used, explain why. Interpret the results. In a random sample of 11 mortgage institutions, the mean interest rate was 3.55% and the standard deviation was 0.41%. Assume the interest rates are normally distributed Which distribution should be used to construct the confidence interval? A. Use a t-distribution because the interest rates are normally distributed and o is known. B. Use a t-distribution because it is a random sample, o is unknown, and the interest rates are normally distributed O C. Use a normal distribution because the interest rates are normally distributed and o is known. @ D. Use a normal distribution because n