The quality of services offered by public schools varies enormously from place to place.

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And indeed, broadly speaking, modern intensive fish farming does harm the environment, although the extent varies enormously.

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On both sides of the Atlantic the frequency of price changes varies enormously.

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If your weight is excessive then the implication is that the excess is fat and, of course, people's body composition varies enormously and BMI doesn't know anything about that so it's a very imprecise index when applied to individuals.

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