For $\mathbf{v}=2 \mathbf{i}+3 \mathbf{j}$ and $\mathbf{w}=3 \mathbf{i}-2 \mathbf{j}$ :
(a) Find the dot product $\mathbf{v} \cdot \mathbf{w}$.
(b) Find the angle between $\mathbf{v}$ and $\mathbf{w}$.
(c) Are the vectors parallel, orthogonal, or neither?