Given $w = g(x, y, z) = 5x - y + 4z$ and
$x(r, s, t) = \frac{r}{s - t}$,
$y(r, s, t) = e^{6s + r}$ and
$z(r, s, t) = \tan(rt)$.
Evaluate $\frac{\partial w}{\partial s}$. Write answer in terms of the independent variables.
$\frac{\partial w}{\partial s} = $