Answer:
you should avoid asking them about their past.
i hope this helps lol, have a great rest of your night !:)
Explanation:
Answer: A
Explanation: The blood–air barrier (alveolar–capillary barrier or membrane) exists in the gas exchanging region of the lungs. It exists to prevent air bubbles from forming in the blood, and from blood entering the alveoli. ... The barrier is permeable to molecular oxygen, carbon dioxide, carbon monoxide and many other gases.
