we have f(x)=15.2^x we have f(6)=960 
It means we at x=6 the population of frog is 960 where the x is meant for sixth week .
so the correct option is D )the number of weeks that have passed
 
        
                    
             
        
        
        
What’s the question asking??
        
                    
             
        
        
        
Trick question Pie can never be equal Pie is Unlimted
        
             
        
        
        
7/15, 0.65, .0715
7/15 = .467
Hope this helps you! (:
-PsychoChicken4040