<span>Air pollution is the presence of harmful substances in the earths atmosphere </span>
        
             
        
        
        
Answer:
Y= 98, 0% , Z = 94,7 %
Explanation:
We use simple 3 rules to find the percentage of purity, using mass data:
Sample Y = 
85g----100%
83,30g----X = (83,30gx 100%)/ 85g= 98, 0%
Sample Z = 
95g----100%
90g----X = (90gx 100%)/ 95g= 94, 7%
 
        
                    
             
        
        
        
The biosphere is made up of all living things (organisms). 
The biosphere includes animals, biomes, population, communities, and ecosystems. The biomes are climate regions which can contain certain types of animals and plants. An ecosystem is all living things in one specific area, also such as plants, animals, and organisms. 
        
                    
             
        
        
        
I am generally confused as to of what you are asking. Can you post something so i can see what you need? I just am confused.