$$
\begin{array}{l}{\text { Assume that } z=f(x, y), \quad x=g(t), \quad y=h(t), \quad f_{\prime}(2,-1)=3} \\ {\text { and } f_{y}(2,-1)=-2 . \text { If } g(0)=2, h(0)=-1, g^{\prime}(0)=5, \text { and }} \\ {h^{\prime}(0)=-4, \text { find }\left.\frac{d z}{d t}\right|_{t=0}}\end{array}
$$