This week's CR4 Challenge Question
You partially fill (up to ½ of its height) a bucket with apples of various sizes. Shake the bucket for several minutes. You notice that the biggest apples are on top. Why?
And the Answer is....
The larger apples cannot slip downward if the available space between the lower apples is not big enough. However apples smaller than the available space can slip down and larger apples will remain on top. By shaking the bucket several times, this process is repeated (smaller apples slip down, bigger apples remain on top), and eventually the system will settle such that the larger apples remain on top.

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