To calculate Defect Removal Effectiveness (DRE) for each phase, we can use the formula: DRE = (Total Defects Injected - Total Defects Escaped) / Total Defects Injected Using the data provided, we can calculate the DRE for each phase as follows: Requirement Phase: Total Defects Injected = 20 Total Defects Escaped = 20 DRE = (20 - 20) / 20 = 0 Design Phase: Total Defects Iniected = 34 Total Defects Escaped = 32 DRE = (34 - 32) /