contrast is probably the first. the seasons of the tree are shown side by side yet so different. the second is gradation. because the colors are creating a gradient across the image. I can not see the rest.
A vantage point is used in linear perspective as a stationary point from which a viewer is related to the object/figure being rendered. It can be thought of as the point of reference from which all things in the artwork can be related to. The vantage point may be very high or very low. High = bird's-eye-view.
