Use the standard norml 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 23 mortgage institutions,the mean interest rate was 3.65% and the standard deviation was 0.46%. Assume the interest rates are normally distributed.
Which distribution should be used to construct the confidence interval?
A. Use a normal distribution because the interest rates are normally distributed and σis known.
B. Use a t-distribution because it is a random sample, σ is unknown, and the interest rates are normally distributed.
C. Use a normal distribution because n < 30 and the interest rates are normally distributed.
D.Use a t-distribution because the interest rates are normally distributed σis known.
E. Cannot use the standard normal distribution or the t-distribution because σis unknown, n <30, and the interest rates are not normally distributed.