11.7 The Organization for Economic Co-operation and Develop- ment (OECD) is an international organization that works to build better policies for better lives. The file Oil contains the three main regions under the OECD's oil demand (in million barrels per day) for the four quarters in 2018. Quarter Americas Europe Asia Oceania 25.3 8.5 14.1 2 25.4 7.6 14.2 3 25.8 7.6 14.6 25.7 8.2 14.3 Source: Data extracted from International Energy Agency Oil Market Report: 13 December 2018, https://www.ica.org/oilmarketreport/ reports/2018/1218/ a. At the 0.05 level of significance, is there evidence of a differ- ence in the mean oil demand among the three regions? b. If the results in (a) are appropriate, determine which region's oil O demand differ in mean. c. At the 0.05 level of significance, is there evidence of a difference in the variation in the mean oil demand among the three regions? d. Which region differs in the demand for oil? Explain.