<span>Air enters through the nose or mouth (which join to form the nasopharyngeal cavity). The air travels through the trachea which and the trachea splits into two bronchi. The air travels through the bronchi which split into smaller and smaller bronchioles. The tiny bronchioles and the air ends up in the miniscule alveoli, where the oxygen in the air diffuse into the bloodstream. Carbon dioxide diffuse from the bloodstream into the alveoli and the unwanted gas travels in reverse back to the nose and mouth, where it is breathed out.</span>
I would say Na. Oxygen has 2 valence electrons and when reacting with other molecules, the ones with the fullest or emptiest shells will react the least. Both H2 and Na are in the Alkali Metals in the first row, but since H2 has 2 molecules, it would use more oxygen than Ana
1. Rocks near mid-ocean ridge were younger than rock near trenches.
2. Matching bands of magnetic rocks were found on either side the mid-ocean ridge; record changes in earth's magnetic field over a period of time.
3. E<span>arthquake data showed oceanic crust is sinking on to the mantle at the trenches.</span>