Commute times in the U. S. are heavily skewed to the right. We select a random sample of 500 people from the 2000 U. S. Census who reported a non-zero commute time. In this sample, the mean commute time is 28.4 minutes with a standard deviation of 18.9 minutes. Can we conclude from this data that the mean commute time in the U. S. is less than half an hour? Conduct a hypothesis test at the 5% level of significance. What is the p-value for this hypothesis test?