???????????????????????????????????????????????????? m g 3/15 ????????????????????? m mg 3/50 ???????????????????????????? y L y Ly L 1 21?????????? 997 .0??) (???? 1211?????????? 98 .0 2??????????????????????????? m???~5?~10??~20??~40???????????????????????????????????????????????????????????????? dd i c ni????)()( 1????? 93 .0121 .099 .023 .0 96 .025 .0925 .017 . .0?????????? + ?????????????
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