What process occurs at the boundary between the capillaries and the alveoli?

Diffusion.

Explanation:

Oxygen in the lungs diffuses from the alveoli into your bloodstream through capillaries and carbon dioxide diffuses from the bloodstream into the lungs also through these capillaries. The carbon dioxide is then breathed out.

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a. possible errors

d. new questions

explanation:

predictions and planning happen before. a summery comes after. errors you get after investigation and new questions propose what you can look for in the future.