(3 points) Two different vaccines (Brand A and Brand B) are available for an infectious disease. Both vaccines provide protection to the disease for several months, until the efficacy begins towane A claim is made that the mean protection time (in days) for Brand A is higher than for Brand A sample of 147 patients that received Brand Als studied. Their mean protection time was 124 8 days with standard deviation 6.9 days. A sample of 161 patients that received Brand B had mean protection time 122.1 days with standard deviation 6.4 days What is the test statistic for this hypothesis test: At the 5% significance level, we can conclude that? ? the mean protection time for Brand Aisn't higher than for Brand B Note: You can earn partial credit on this problem the mean protection time for the two Brands is the same the mean protection time for Brand Ais higher than for Brand B. Preview My Answers Submit Answers we cannot draw any conclusions at all the mean protection time for Brand B is higher than for Brand A You have attempted thin problem otimes. You have 3 attempts remaining. Email Instructor