Earth's atmosphere is 78% nitrogen, 21% oxygen, 0.9% argon, and 0.03% carbon dioxide with very small percentages of other elements. Our atmosphere also contains water vapor. In addition, Earth's atmosphere contains traces of dust particles, pollen, plant grains and other solid particles.
        
                    
             
        
        
        
Answer:
5
Explanation:
Nucleus is the center or "CEO" of the cell, that holds the cell's DNA and controls the cells' function.
 
        
                    
             
        
        
        
Answer:
Compound
Explanation:
compound: Substance that is made up of more than one type of atom bonded together
mixture: a combination of two or more elements of compound which are not chemically bonded
 
        
                    
             
        
        
        
I believe it’s the last option