A large school district held a district-wide track meet for all high school students. For the 2-mile run, the population of female students participating follows a Normal distribution and had a mean running time of 8.8 minutes with standard deviation of 3.3 minutes. The population of male students participating also follows a Normal distribution and had a mean running time of 7.3 minutes with standard deviation 2.9 minutes. Suppose 8 female students and 8 male students who participated in the 2-mile run are selected at random from each population. Let xF represent the sample mean running time for the female students, and let xM represent the sample mean running time for the male students. a. Find and interpret the mean and standard deviation of the sampling distribution of the difference in sample means xF − xM. b. Find the probability of getting a difference in sample means xF − xM that is less than 0.