An article in the American Journal of Emergency Medicine com pa red the ability to detect acute traumatic aortic injury [ATAIJI on cervical xray images. The data consisted of 13 cases of ATAI, 19 cases with negative aortography [NAG] and 18 cases with multiple trauma (MT) without aortographv. Measurements of the cervical softtissue width at the third cervical vertebrae generated the following results. Averages were 8.4, 8.8 and 6.2 mm and standard deviations were 3.1, 2.6 and 2.9 mm for the ATAI, NAO, and MT groups, respectively. Consider an ANOVA for these data. a} Use the sample sizes and group averages to compute the grand mean width and the mean square for treatments. Round your answer to two decimal places (e.g. 9.87}. MSTreaLmean = n b] Use the sample sizes and standard deviations in the groups to compute the mean square error. Round your answer to two decimal places (e.g. 9.87). MSError : I c} Use the results in the previous parts to conduct the ANOVA test and prove that the mean widths do not differ. Calculate the Pvalue for the test. SS MS F P Source DF (to two (to two (to two (to th ree decimal places] decimal places} decimal places] decimal places} a a n n n a a a Total n a