Use the standard normal distribution or the t-distribution....

Use the standard normal distribution or the t-distribution to construct a 90% condence interval for the population mean. Justify your decision. If neither distribution can be used, explain why. Interpret the results. In a random sample of 22 mortgage institutions, the mean interest rate was 3.61% and the standard deviation was 0.38%. Assume the interest rates are normally distributed. Which distribution should be used to construct the condence interval? 0 A. Use a t-distribution because the interest rates are normally distributed and o' is known. 0 B. Use a normal distribution because n