In a room with one small window, Zephyr is standing directly in front of the window with the sun behind him, while Indigo is standing facing Zephyr. Will Indigo be able to see Zephyr's face clearly, and why?

Make your response very short.
Indigo will have difficulty seeing Zephyr's face clearly. The sunlight coming through the small window from behind Zephyr will create a backlighting scenario, where Zephyr's face is in shadow relative to the bright light surrounding his silhouette. This contrast makes it hard for Indigo's eyes to adjust to both the bright light of the sun and the relative darkness of Zephyr's face, so Indigo will mostly see Zephyr's silhouette rather than clear facial features.