Can you explain how to get all of these questions in great detail (ones in red highlight)? I have the answers but I don't know how they got them.

39. Because his screen is negative we know there is an 84% chance he does not have oropharyngeal cancer. Questions 12-24: Chung and Hwang (2008) examined the difference between an experimental and a control group of patients with leukemia. The experimental group received two follow-up phone calls after discharge, and the control group received routine care. Their Table 2 is reproduced here as Table 9 6. TABLE 9-6 Test of Two-Group Differences 4 Weeks after Discharge Experimental Group control Group (N = 35) (N = 35) Variable SD SD Self-care 2.67 0.36 1.78 0.38 10.347" Symptom distress 0.34 0.21 0.82 0.51 5.158" Quality of life 70.46 18.76 64 15 16.01 6.074" "P