What is special about nitrogen and what is the main function in the atmosphere?

Nitrogen is special because it is necessary for growth and reproduction. It's needed for plants and animals to survive. The main function for the atmosphere i believe is to give oxygen and nitrogen.

Nitrogen is what humans exhale and the main function is nitrogen and oxygen, nitrogen takes up 78% of the atmosphere, oxygen takes up 21%

The speed of  sound:   sound travels  at different speeds depending on what it istraveling through. of the three mediums (gas, liquid, and solid)  sound waves travel the slowest through  gases, faster  through  liquids, and fastest  through  solids.