I haven't really given time in Middle-earth reckoning much thought (beyond the Hobbitish calendar craze), but at first blush one would think that, relatively speaking, time (as far as seconds, minutes and hours) would be a fairly useless construct for Elves; however, I suppose time-segmentation would still be required by the Eldar. After all, Lembas takes 12-13 minutes to bake at 400 degrees.
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