How much oxygen is available if the emergency oxygen is pulled?

The correct answer reflects the typical duration of emergency oxygen availability in many aviation or emergency situations. When the emergency oxygen system is deployed, it generally provides sufficient oxygen for a standard duration that allows individuals to safely breathe while they address the situation or evacuate.

In this case, the choice of 10 minutes suggests that this is the standardized amount of oxygen provided in the event of an emergency. This duration is intended to give users adequate time to manage their circumstances, whether that involves stabilizing themselves in a cabin environment where oxygen levels may be compromised or enabling a safe egress from the aircraft or area of concern.

Oxygen systems are designed to be effective but also limited, ensuring that they provide necessary assistance without extending beyond the capacity of the system. Therefore, having access to 10 minutes of usable oxygen is a crucial safety feature that aligns with standard operational procedures in emergency situations.