Chapter 6, Section 13, Exercise 286 Testing the Effects of Tea on the Immune System We have seen that drinking tea appears to offer a strong boost to the immune system. In a study extending the results,1 blood samples were taken on 5 participants before and after one week of drinking about five cups of tea a day (the participants did not drink tea before the study started). The before and after blood samples were exposed to e.coii bacteria, and production of interferon gamma, a molecule that fights bacteria, viruses, and tumors, was measured. Mean production went from 155 pg/mL before tea drinking to 448 pg/mL after tea drinking. The mean difference for the 5 subjects is 293 pg/mL with a standard deviation in the differences of 242 . The paper implies that the use of the I -distribution is appropriate. Use the information to test whether mean production of interferon gamma as a response to bacteria is signicantly higher after drinking tea than before drinking tea. Use a 5% significance level. 1Adapted from Kamath, A., et. al., \"Antigens in tea-beverage prime human VyZVGZ T cells in vitro and in vivo for memory and non-memory antibacterial cytokine responses,\" Proceedings of the Nationai Academy of Sciences, May 13, 2003; 100(10): 6009- 6014. Give the test statistic and the ID -value. Round your answer for the test statistic to two decimal places and your answer for the P -value to three decimal places. test statistic = p -value Give the conclusion using a 5% significance level. Reject H0 . 0 Do not reject H0 . Is there evidence that mean production of interferon gamma is higher after drinking tea? 0 Yes