Multiple choice general knowledge science & technology

Exhaled air has what % of its oxygen left?

  1. 77%

  2. 26%

  3. 48%

  4. None

Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Exhaled air typically contains 15-19% oxygen, compared to 21% in inhaled air. This means roughly 75-90% of the original oxygen remains. Options A (77%), B (26%), and C (48%) are all incorrect values.