\( W(s, t)=F(u(s, t), v(s, t)) \), where \( F, u \), and \( v \) are differentiable. If \( u(-5,-2)=-8, u_{s}(-5,-2)=-5, u_{\mathrm{l}}(-5,-2)=5, v(-5,-2)=6 \), \( v_{s}(-5,-2)=8, v_{2}(-5,-2)=-1, F_{u} (−8,6)=−4, and F_{v} (−8,6)=7, then find the following: Ws(−5,−2)= Wt (−5,−2)=