The above painting is what I came up with. The left panel has a light foreground, mid-tone middle ground, and dark sky; the center panel has a mid-tone foreground, dark middle ground, and light sky; and the right panel has a dark foreground, mid-tone middle ground, and light sky. As it happens, the left panel has the feeling of an early morning; the center panel, that of the mid-afternoon; and the right panel comes across as a scene at dusk. How about that! Good teachers exercise our mind and force us to grow. Thank you, Carolyn.