Scores for a common standardized college aptitude test are normally distributed with a mean of =508=508 and a standard deviation of =111=111. Randomly selected women are given a Test Preparation Course before taking this test. Assume, for sake of argument, that the test has no effect. If 12 of the women are randomly selected, find the probability that their mean score is at least 578.5. P(M>578.5)=P(M>578.5)=