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Example 6.15 (page 383) gives a test of a hypothesis about the mean consumption of sugar sweetened beverages at your university based on a sample of size n:100. The hypotheses are H02u=286 Hana-#286 While the result was not statistically signicant, it did provide some evidence that the mean was smaller than 286. Thus, you plan to recruit another sample of students from your university but this time use a one- sided alternative. You were thinking of surveying n:100 students but now wonder if this sample size gives adequate power to detect a decrease of 15 calories per day to u=27l. (a) Given u:0.05, for what values of 2 will you reject the null hypothesis? (b) Using 0:155 and u=286 for what values of Xi will you reject H0? (c) Using 0:15 5 and u=271, what is the probability that x_ will fall in the region dened in part (b)? (d) Will a sample size of n=100 give you adequate power? Or do you need to nd ways to increase the power? Explain your answer. (6) Use the Statistical Power applet to determine the sample size n that gives you power near 0.80