A company wants to determine whether its consumer product ratings (0-10) have changed from last year to this year. The table below shows the company's product ratings from eight consumers for last year and this year. At a 0.05, is there enough evidence to conclude that the ratings have changed? Assume the samples are random and dependent, and the population is normally distributed. Complete parts (a) through (f). Consumer 1 2 3 4 5 6 7 8 D Rating (last year) 5 8 2 2 5 9 6 5 Rating (this year) 1 4 2 3 5 7 3 3 (c) Calculate d and sa d= (Type an integer or a decimal. Do not round.) Calculate Sa Sd (Type an integer or a decimal. Round to three decimal places as needed.). (d) Use the t-test to find the standardized test statistic t t= (Type an integer or a decimal. Round to three decimal places as needed.)