93-100 A+ 4.0
88-92 A 3.7
83-87 A- 3.3
78-82 B+ 3.0
72-77 B 2.7
68-71 B- 2.3
63-67 C+ 2.0
58-62 C 1.7
53-57 C- 1.3
50-52 D 1.0
40-49 F 0
39以下 O 0
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上面三项分别是分数、成绩等级和GPA
