6. College Presidents There are about 4200 college presidents in the United States, and they have annual incomes with a distribution that is skewed instead of being normal. Many different samples of 40 college presidents are randomly selected, and the mean annual income is com- puted for each sample. a. What is the approximate shape of the distribution of the sample means (uniform, normal. skewed, other)? b. What value do the sample means target? That is, what is the mean of all such sample means? In Exercises 7-16:use the same population of (4, 5, 9) that was used in Examples 2 and 5