(Still focusing on the study that found Americans worked an average of 2,070 minutes per week). Without any prior expectations, you want to see if aircraft pilots work different amounts of time per week than the national average. You nd in a sample of 30 pilots, the average amount worked per week was 1,410 minutes with a standard deviation of 213 minutes. Use the critical- value approach for a ttest (where it = .05) to determine if there is a signicant difference in amount of time worked per week between the national average and pilots. List your degrees of freedom List your t test statistic List your critical tvalue(s) Is the difference between the national average and pilots statistically signicant? (Y es/N 0) 999?\