(15 pts.) You are tasked with estimating the difference in student monthly rent prices between renting a two-bedroom apartment in State College (S) versus Bellefonte (B). From a sample of 20 such available apartments in both towns, the following sample data, in dollars, was obtained:

= 1360 = 80 = 1175 = 40

Based on this information, what is a 90% confidence interval for the difference in YEARLY cost of renting a two-bedroom apartment between State College and Bellefonte? Provide an interpretation of your interval. What would need to be true for you results in part A to be statistically valid?