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A study was carried out to determine if Reiki touch therapy was useful in the reduction of average pain levels in chronic pain sufferers. The pain level reported by a random sample of 8 patients before and after the therapy session is shown below. Test whether there has been a reduction in pain after the therapy using a significance level a = 0.05. Patient 1 2 3 4 5 6 7 8 Before 6 2 2 3 3 4 2 5 After 3 O 2 1 2 1 What is the null hypothesis for this study? OHo : H > 0 OHo : M = 0 OHo : M