How much time do you have to don and use your oxygen mask?

The correct amount of time to don and use an oxygen mask in an emergency situation is indeed 5 seconds. This quick response time is critical because in the event of cabin depressurization, the atmosphere can change rapidly. Pilots and crew are trained to react swiftly to this kind of emergency, ensuring that they can maintain a safe environment for themselves and the passengers.

The 5-second requirement emphasizes the need for readiness and proficiency in emergency procedures. Crew members practice this effectively to ensure they can respond without hesitation or delay, as every second counts in preventing hypoxia and maintaining cognitive function during high-altitude emergencies.

The other options suggest longer response times, which could lead to dangerous situations where crew members might not secure oxygen in a timely manner, potentially jeopardizing their operational abilities in a critical situation.