Use the standard normal distribution or the t-distribution to construct a 90% 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 14 mortgage institutions, the mean interest rate was 3.59% and the standard deviation was 0.44%. Assume the interest rates are normally distributed. Which distribution should be used to construct the confidence interval? O A. Use a normal distribution because n