Explanation:
A model is used to help scientists visualise things that they cannot actually see. It can be thought of as a thinking tool, to help form explanations. Models are useful simplifications to aid understanding. ... It can then be used to explain further phenomena and to make predictions of future behaviour.
Answer:
If you were to ask me I would say that your answer is C
Explanation:
Alveoli are part of the reparation system found in the lungs. They are covered in capillaries. In Alveoli, oxygen diffuses from the air into the blood vessels surrounding the alveoli and carbon dioxide from the body diffuses from blood into the alveoli’s air spaces. Alveoli clump together and form sacs.
The answer is carbon, hoped this helps you!
I think it is in Tales of Suspense #39 that the cover dated March 1963. May 1968 Iron Man #1 received its own title.