Ozone, a special form of oxygen that screens out harmful ultraviolet rays, reaches high concentrations twelve miles above Earth, where it has long appeared that it was immune from human influence; we have now realized, though, that emissions of industrial chlorofluorocarbons deplete the ozone layer.
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Ahas long appeared that it was immune from
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Bhas long appeared to have been immune from
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Chas long appeared as being immune to
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Dhad long appeared immune to
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Ehad long appeared that it was immune to
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