For each set of circumstances in table 12-3, indicate whether the observed value is sufficient to assert statistical significance.

TABLE 12-3 _ Finding Statistical Significance Using the t-Distribution Number of Tails in Test Confidence Level Degrees of Freedom t-Observed t-Critical Statistically Significant Two 99% 21 2.95 2.831 yes Two 95% 25 -3.10 Two 95% 15 -2.12 Two 90% 10 1.94 Two 90% 18 1.57 One 99% 12 -2.46 One 99% 23 2.38 One 98.5% 40 -2.30 One 95% 28 1.89 One 95% 16 1.68