Q:Question:In 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 percentages, notA:Answer:See a step by step answer