From the results of a survey conducted by the U.S. Bureau of Labor Statistics [A-9], it was estimated that 21 percent of workers employed in the Northeast participated in health care benefits programs that included vision care. The percentage in the South was 13 percent. Assume these percentages are population parameters for the respective U.S. regions. Suppose we select a simple random sample of size 120 northeastern workers and an independent simple random sample of 130 southern workers.

What is the probability that the difference between sample proportions, ^p1 ^p2, will be between .04 and .20?