R is a velocity of measure, defined as a reasonable speed of travel that is consistent with health, mental well-being, and not being more than, say, five minutes late. It is therefore clearly as almost infinite variable figure according to circumstances, since the first two factors vary not only with speed as an absolute, but also with awareness of the third factor. Unless handled with tranquility, this equation can result in considerable stress, ulcers, and even death.
Douglas AdamsThe party and the Krikkit warship looked, in their writhings, a little like two ducks, one of which is trying to make a third duck inside the second duck, whilst the second duck is trying very hard to explain that it doesn't feel ready for a third duck right now, is uncertain that it would want any putative third duck anyway, and certainly not whilst it, the second duck, was busy flying.
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