A healthcare provider initiates ventilations to ensure adequate breathing and oxygenation. While ventilations are being performed, capnography is established to evaluate the adequacy of the ventilations. The healthcare provider determines that ventilations are adequate based on which end-tidal carbon dioxide (ETCO₂) value?
1) 20-30 mmHg
2) 35-45 mmHg
3) 50-60 mmHg
4) 65-75 mmHg