Q:Question:order to estimate the mean 30-year fixed mortgage rate for a home loan in the United States, a random sample of 21 recent loans is taken. The average calculated from this sample is 4.50%. It can be assumed that 30-year fixed mortgage rates are normally distributed with a population standard deviation of 0.3%. Compute 90% and 95% confidence intervals for the population mean 30-year fixed mortgage rate. (You may find it useful to referenceA:Answer:See a step by step answer