640
0
21
455
0
21
722
0
21
799
1
21
320
0
21
592
0
21
873
0
21
741
0
21
818
0
21
618
2
21
920
0
21
698
0
21
1351
2
21
405
5
21
968
0
21
655
4
21
676
2
21
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Keyword(s): 数学 中2