???????????????2?? ??????30??????????? ??????2???????

??????1P=10?? ???1-1?? ???1+1??

?????1??=14 2??=20 3??=24.7 4??=28.7 5??=32.3

6??=35.7 7??=38.8 8??=41.8 9??=44.7 10??=47.5

11??=50.2 12??=52.8 13??=55.3 14??=57.9 15??=60.3

16??=62.7 17??=65.7 18??=67.5 19??=69.8 20??=72.1

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