Answer:
An old penny rusting
Explanation:
A penny forming rust is the penny being chemically altered and changing form as opposed to dissolving sugar in water, which is still sugar, just mixed with water. It doesn't change the chemical makeup of the water or sugar.
 
        
             
        
        
        
All you would have to do is sum them up cause their going the same direction.
        
                    
             
        
        
        
Answer:
Limiting human use of nitrogen that is in the atmosphere.
Explanation:
 
        
             
        
        
        
Carbon is the atom, which is necessarily find in the living organism. 
All the living organisms are made up of biomolecules. All the biomolecules are organic compounds. The substance cannot be consider as living, if it lacks nucleic acids. There are two types of nucleic acids DNA (deoxyribonucleic acid) and RNA (ribonucleic acid), both have a structure made up of carbon rings and chains.
Other than nucleic acids, proteins, enzymes, hormones etc are also made up of carbon. So, all the living cells, or dead remain of organism must have carbon atom.
Hence, the correct answer is option D. carbon.
 
        
             
        
        
        
Hey there!
Your Answer: Risk Assessment
Hope it helped!!!☺️