Answer:
If you want to know who you are, look among your friends. Healthy relationships help us see problems clearly, and can help us develop solutions.
Explanation:
Internal and external.
Hi there!! Cilia are very small fine hairlike projection's/tissues, who's primary responsibilities in the airway is to make sure that it is clear. To be more specific... Cilia line the airways' trachea down. These cilia will do two things; They will trap germs and particulate matter (dust, dander, etc..), before then moving the trapped objects upward to the area where the airway meets the larynx, where you then swallow it... Additionally you can expel it eventually with a cough.
