Answer:
It is important that he human trachea is reinforced with cartilaginous rings to keep the passage open as pressure keeps fluctuating during the process of breathing.
Explanation:
The trachea is reinforced with cartilaginous rings as it doesn't allow the trachea to collapse in our day to day lifestyle. It also keeps the air way passage open in spite of the continuous pressure changes during breathing.
The rings are not complete posteriorly to provide another advantage, that is it allows the esophagus to expand anteriorly ( inside the body) when we swallow food.
Agree on using one system. That way no one would be confused by the measurements and everyone would have the same calculations without having to painfully convert. Preferably the metric since it was designed to be easy
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