Final answer:
The compression-ventilation ratio for 2-rescuer adult, child, and infant CPR is 30:2, 30:2, and 15:2 respectively.
Step-by-step explanation:
The compression-ventilation ratio for 2-rescuer adult CPR is 30 compressions to 2 breaths. For child CPR, the ratio is also 30 compressions to 2 breaths. For infant CPR, the ratio is 15 compressions to 2 breaths. The compression-ventilation ratio for 2-rescuer CPR in adults is 30:2, meaning 30 compressions are followed by 2 ventilations. For a child or an infant, the ratio is the same when performed by healthcare providers or trained rescuers. Significant emphasis is placed on performing high-quality chest compressions to ensure that blood is adequately circulated to vital organs like the brain.