Answer:
The boundary between two air masses that have different temperatures or humidity. In the mid-latitude areas of the Earth, where warm tropical air meets cooler polar air, the systems of fronts define the weather and often cause precipitation to form.
Explanation:
Scientific definition for front
<span>macromolecule, cell, tissue, organ, organ system</span>
Inhaled oxygen moves from the alveoli to the blood in the capillaries, and carbon dioxide moves from the blood in the capillaries to the air in the alveoli. This is what happens in the alveoli during gas exchange
The answer is B cell wall
I think it's the first and second option but I could be wrong because I don't know much about deserts :)
