Answer:
   see attached
Step-by-step explanation:
To find the inverse function, solve ...
   x = f(y)
   x = (y^7)/7 -4 . . . . . . . use the definition of f(x)
   x +4 = (y^7)/7 . . . . . . add 4
   7(x +4) = y^7 . . . . . . multiply by 7
   (7(x +4))^(1/7) = y . . take the 7th root
The inverse function is the one shown in the attachment.
 
        
             
        
        
        
First, find the volume of the whole cube
Volume of cube = 4 x 4 x 4 = 64 cm³
The volume of sand is 25% of the volume of cube so,
Volume of sand = 25/100 x 64 = 16 cm³
        
             
        
        
        
The vertex is (-4,-3)
The axis of symmetry is x=-4
and the transformations are:
 
        
             
        
        
        
They will have played with 19 loses 76 wins !