When fluorine from the air ends up in water it will settle into the sediment. | Diễn Đàn Tuổi Trẻ Việt Nam Uhm.VN When fluorine from the air ends up in water it will settle into the sediment.
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When fluorine from the air ends up in water it will settle into the sediment. | Diễn Đàn Tuổi Trẻ Việt Nam Uhm.VN