Final answer:
The sky is generally the deepest blue just after a rainstorm, as the rain clears the atmosphere of dust particles, leading to optimal conditions for light scattering, which is what makes the sky appear blue.
Step-by-step explanation:
The sky is usually the deepest blue just after a rainstorm. The reason is that a rainstorm often clears the atmosphere of dust particles, creating optimal conditions for light scattering. When sunlight passes through the atmosphere, it collides with particles and molecules, scattering it in all direction. This scattering of light is what makes the sky appear blue. However, the color of the sky can vary significantly depending on the time of day, weather conditions, and geographical location. But in general, it tends to be the deepest blue immediately following a rainstorm because of the clear, dust-free air.
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