Samples of final examination scores for two statistics classes with different instructors provided the following results: For instructor "A" the sample size was 12, the sample mean score was 73 and the sample standard deviation was 6. For instructor "B" the sample size was 15, the sample mean score was 78 and the sample standard deviation was 8. At a 5%(0.05) level of significance, test whether these data are sufficient to conclude that the mean scores for the two classes are the same? What is your conclusion?