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2019 12 23( 1), 2019 12 15( 2), 2019 12 9( 3) : 2020 3 2 . . 1. 2. . 1. 49 2. 49 3. 76 4. 76 . . 106 15 1(2020 3) . 2011 , 2012 3 , 2014 . . , , 50 (Rmb) 100 (Rmb)
Hyoyoung Koo (Tue,) studied this question.