Independent random samples from two regions in the same area gave the following chemical measurements (ppm). Assume the population distributions of the chemical are mound-shaped and symmetric for these two regions. Let mu subscript 1 be the population mean for x subscript 1 and mu subscript 2 be the population mean for x subscript 2 . Suppose the confidence interval for mu subscript 1 minus mu subscript 2 for a specific level of confidence is - 30.77 to 2.25. Does the interval consist of numbers that are all positive? all negative? or different signs? At the given level of confidence, is one region more interesting than the other from a geochemical perspective