M^3n^-6p^0 simplify expression use positive exponents

N^-6 should be written   n^(-6).  This is equivalent to    

 1

n^6

Also, p^0 is equivalent to 1.

Thus, 
                              m^3 (1)         m^3
M^3n^-6p^0   =   =
                                n^6              n^6

and this could be written in the alternative form (m / n^2)^3, or

          m
      ( )^3
         n^2

The correct graph is the second one, with the points being at (-6,0), (2,0) and reaching down to (-2,-8)

If you make it a little more clear i can answer it