Gold, Silver, Copper are all part of a class of minerals called Native Elements. Platinum, Graphite, Diamond and Mercury are also apart of this group. Also known as the Native Metals.
        
             
        
        
        
I can help you! What is your question?
        
             
        
        
        
The answer for the question is c.
        
             
        
        
        
Answer: 8 moles 
Explanation: 
Nc2H6= 4 mol
2C2H6 + 7O2 → 4CO2+6H2O
CO2=4/2⋅4
NCO2= 8 moles 
( I write this on paper so the letters and format might be confusing) sorry!!