2.1.4 Maxima

A grade: { 2, 4, 5, 6, 7, 9, 11, 12, 13, 14, 15, 16, 17, 18 }

B grade: { 1, 3, 8, 10 }

C grade: { }

F grade: { 19, 20, 21, 22, 23 }