Start by taking out the bracket in the numerator: where we have (a^b)^c, this is equivalent to a^(b*c). So that's x^9, y^-6, z^12, w^15.
The denominator has two z's? You'll want to combine terms first: where we have (a^b)*(a^c), this is equivalent to a^(b+c). So that's z^(2-3), or z^-1.
Finally we reach the actual division step: where we have (a^b)/(a^c), this gives us a^(b-c). Thus: (x^9)/(x^2) = x^7, (y^-6)/(y^-3) = y^-3, (z^12)/(z^-1) = z^13, and w isn't in the denominator so that's just w^15.