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As part of a large, ongoing diet study, some subjects of the study are taking part in an intensive exercise program for four weeks. Several variables are measured on these subjects, both at the beginning and at the end of the four-week period. Some of these variables are weight, cholesterol, and triglyceride level. One objective of this particular study is to assess the effect of diet and intense exercise on increasing triglyceride levels. The data for a simple random sample of nine of these subjects are given in the table below. Subject 1 2 3 4 5 6 7 8 9 Initial level 180 139 112 167 138 160 156 94 145 Level after 4 weeks 100 92 82 171 132 123 92 121 159 Difference 80 47 30 4 6 37 64 -27 -14 The data are to be analyzed using the Wilcoxon signed rank test. The objective of this study is to assess if diet and intense exercise increase triglyceride levels. If the test statistic W were to be based on positive differences, what the P-value for this test and what is the decision at 0.01 significance level? The mean and the standard deviation of W are found 22.5 and 8.44 respectively