8.25 It has been reported that 40% of U.S. workers employed as purchasing managers are females. In a simple random sample of U.S. purchasing managers, 70 out of the 200 are females. Given this information: Source: Bureau of the Census, Statistical Abstract of the United States 2009, p. 384.

a. What is the population proportion, ?

b. What is the sample proportion, p?

c. What is the standard error of the sample proportion?

d. In the sampling distribution of the proportion, what is the probability that a sample of this size would result in a sample proportion at least as large as that found in part (b)?