Each term is double the one before it, so the appropriate choice is ...
... D. f(x+1) = 2f(x)
 
        
                    
             
        
        
        
Answer:
ah theres no picture m8 put a picture of the shapes your talking about and I could help ya out
 
        
                    
             
        
        
        
The more expensive bike could be a bigger size so in stead of being a 20 inch it could be a 24 inch, another option is that one bike is made by a lower brand name company hile the expensive one is a better well know company so in that case the extra $100 is just a added price for the name. Last option is one's on sell and ones not. I hope this helped! :)