\item \lect Consider the formula $$\phi = \exists x \forall y \; \big( P(x,y) \imp (Q(x,y) \lor R(x,y))\big).$$
Does the following model $\mathcal{M}$ satisfy the formula? \\
            $\mathcal{A} = \{a,b\}$ \\
            $P^\mathcal{M} = \{(a,a),(a,b)\}$ \\
            $Q^\mathcal{M} = \{(a,a),(b,a)\}$\\
            $R^\mathcal{M} = \{(a,a),(b,b)\}$