A physician believes that a person's diastolic blood pressure can be lowered, if, instead of taking a drug, the person performs yoga exercises each evening. Ten subjects are randomly selected. Their blood pressures, measured in millimeters of mercury, are listed below. The 10 patients are instructed in several yoga exercises and told to perform them each evening for one month. At the end of the month, their blood pressures are taken again. The data are listed below. Use the Wilcoxon signed-ranks test to find the critical value to test the physician's hypothesis. Use

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