A beer distributor claims that a new display, featuring a life-size picture of a well-known athlete, will increase product sales in supermarkets by an average of at least 50 cases in a week. For a random sample of twenty supermarkets, the average sales increase was 41.3 cases and the sample standard deviation was 12.2 cases. Assume that the population of beer sales increase is normally distributed. Find the p-value associated with the test statistic.