C) I and III only just got this question on usa test prep and therefore i'm right 
        
             
        
        
        
A scientist is conducting an investigation that involves water, silver, carbon dioxide, and oxygen gas. They are each made of matter. Some are compounds and some are elements. They all contain atoms. [ -best describe all of the materials he is using in the investigation. ]
        
             
        
        
        
Answer:
AlF3 is the formula for aluminum flouride.
Explanation:
 
        
             
        
        
        
Answer:
Adenine 2) Thymine 3) Cytosine 4) Guanine
Explanation: