Nine experts rated two brands of coffee in a taste-testing experiment. A rating on a 7-point scale (1 = extremely unpleasing, 7 = extremely pleasing) is given for each of four characteristics: taste, aroma, richness, and acidity. The accompanying data table contains the ratings accumulated over all four characteristics. Complete parts (a) through (d) below. Click the icon to view the data table. a. At the 0.10 level of significance, is there evidence of a difference in the mean ratings between the two brands? Let py be the mean rating for brand A and u2 be the mean rating for brand B. Determine the null and alternative hypotheses for this test. O A. Ho: HD SO (where HD = H1 - H2) O B. Ho: HD 20 (where HD = H1 - H2) H 1 : HD >0 Hy : HD