Imagine you work as an analyst for a large beverage firm, deciding where to place vending machines to best serve your customers. You want to determine if the average weekly sales generated by the vending machine is below $975. You examine the past 20 weeks of sales with a machine located on the campus of McMaster and find that it had a sample average level of weekly sales of $812.42, with a sample standard deviation of $240.19. Using this information, you want to do a hypothesis test with a 10% significance level. What is the value of your test statistic?