??? ???? ??? ???? ?? ????. ??? ??? ???? ??? ??? ???.
?? ???(0.02%)? ??????? ??? ???? ??? ???? ????? 3? ?? ?? ???. ???(0.06%)? ??? ??? ?? ?? ???? ???? ?? ???. ??? ???? 6?? 23??? 500?? ?? 4?3000?～4?4000???. ???? ??? ??? ???(0.05%) ?? ?? ????.
?? ?? ?? ???? ??? ???(0.03%)? ??? ?? ???? ????. ?? ???(―0.21%)? ???? ? ??? ???? ???? ???? ????. ????2?? 15??? 1500?? ??? 4?～4?1000???.
???(0.16%)? ???(0.47%) ???(0.17%) ???(0.16%) ????, ???(0.05%)? ???(0.18%) ???(0.17%) ???? ?? ???.
??? ???? ??(0.08%) ??(0.07%) ??(0.06%)? ????, ??(―0.01%) ??(―0.09%)? ???? ?? ????. ?????? ??(0.22%) ??(0.20%) ??(0.20%)?? ?? ???.
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