Refer to the American Journal of Sociology (Jan. 2014) study of the characteristics of antiwar demonstrators in the United States, Exercise 2.106 (p. 77). The researchers found that the mean number of protest organizations joined by antiwar demonstrators over a recent 3-year period was .90 with a standard deviation of 1.10. Assume that these values represent the true mean ( and true standard deviation ( of the population of all antiwar demonstrators over the 3 years.

a. In a sample of 50 antiwar demonstrators selected from the population, what is the expected value of x̅, the sample mean number of protest organizations joined by the demonstrators?

b. Find values of the sample mean, L and U, such that P(L < x̅ < U) = .95?