Final answer:
A nonrebreather mask at 12-15 liters per minute can deliver approximately 60-100% oxygen to the patient.
Step-by-step explanation:
A nonrebreather mask set to deliver 12-15 liters per minute of oxygen can supply the patient with about 60-100% oxygen. This mask is equipped with a reservoir bag that is filled with pure oxygen, allowing minimal dilution with exhaled gases and room air. The high flow rate fills the reservoir bag with enough oxygen to meet the high oxygen demand and achieve a high fractional concentration of inspired oxygen (FiO2). The exact percentage can vary due to factors such as the patient's breathing pattern, mask fit, and the exact flow rate used.