??? ??? ????? ??? ?? ???? ?? ???? ?? ??? ???? ??????? ?? ???.

???(0.15%)? ????? ???? ?????????? ??? ??? ??? ???. ??? ??1? 28??? ?? ?? 2500?? ?? 7?～7?3000?? ?, ??1?? 42??? 1000?? ?? 11?3000?～12?3000?? ???. ???(0.81%)? ???(0.50%), ????(0.50%), ???(0.36%) ?? ???? ??? ???. ???, ???, ????? ???? ?? ??? ?? ??? ???? ??. ??? ?????? 56??? 1?7500?? ?? 12?5000?～15?5000?? ?, ??? ????? 38??? 5250?? ?? 6?5000?～7?? ?, ??? ???? 45??? 1000?? ?? 4?～4?4500?? ?? ???? ??.

??(0.07%) ??(0.05%) ??(0.03%) ??(0.01%) ??(―0.05%) ? ???? ??? ????. ?????? ??(0.70%) ??(0.69%) ??(0.32%)? ???? ??. ????? ??? ????? ??? ??7?? 22??? 1500?? ?? 3?3000?～3?4000?? ?? ????.

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