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

?????? ???(―0.05%)? ???(―0.03%)? ?? ????. ‘?? ??’? ???? ??????? ??? ????? ?? ???? ??? ??. ??? ??? ????? 32?? ?? 500?? ??? 2?8000?～3?2000?????.

?????? ?? ????? ????? ??? ???(0.65%) ???(0.38%)? ??? ???(0.20%) ???(0.13%) ???(0.12%)?? ?????. ??? ??? ????? 33??? 1000?? ?? 2?7000?～3?5000?? ???, ??? ?? ??? ???2? ???? 38??? 1000?? ?? 2?1000?～2?3000?? ???.

??(0.05%) ??(0.01%) ??(0.01%) ??(0.00%) ??(―0.02%) ? ???? ?? ??? ????. 50??? ??(―0.07%), 20??? ??(―0.29%)? ?????? ??? ???. ???? ??(0.24%), ??(0.21%), ??(0.20%), ??(0.14%)? ??? ??? ???.

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