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I do not give letter grades on exams, only points. But if I did give letter grades, the diagram above would show where the exam shakes out. For simplicity, this histogram shows the four large grade categories, (A- and A), (B-, B and B+), (C-, C and C+) and (D-, D and D+).
Notice that a large fraction of the class did not pull a passing grade. If you are in that group, you want to modify your study activity.