Answer:
To moisten and to protect the airway from stuff like unknown pathogens and infection
Explanation:
The Trachea also known as the windpipe has tons of 'little hairs' called cilia in the epithelium that protect the throat. When someone smokes or breathes in gases it is destroyed and exposes the trachea. But thats another story. :)
Answer:

Huh? You have already given the answer.......Anyways, the attached picture is an example for a stratus cloud ☁️.
Answer AND Explanation:
Proteins are formed from the translation of mRNA to amino acid. Each set of 3 nucleotides make up a codon that codes for a specific amino acid. Frameshift mutations can also impact the formation of the protein. A change in a nucleotide does not always change the amino acid or protein because some amino acids have more than one set of 3 nucleotides that code for them. Valine, for example, is coded for by GUU, GUC, GUA and GUG. A change in the last nucleotide wouldn't affect the amino acid formed. However,GAG codes for glutamic acid.