x   y  set
10  8.04 a
 8  6.95 a
13  7.58 a
 9  8.81 a
11  8.33 a
14  9.96 a
 6  7.24 a
 4  4.26 a
12 10.84 a
 7  4.82 a
 5  5.68 a
10  9.14 b
 8  8.14 b
13  8.74 b
 9  8.77 b
11  9.26 b
14  8.10 b
 6  6.13 b
 4  3.10 b
12  9.13 b
 7  7.26 b
 5  4.74 b
10  7.46 c
 8  6.77 c
13 12.74 c
 9  7.11 c
11  7.81 c
14  8.84 c
 6  6.08 c
 4  5.39 c
12  8.15 c
 7  6.42 c
 5  5.73 c
 8  6.58 d
 8  5.76 d
 8  7.71 d
 8  8.84 d
 8  8.47 d
 8  7.04 d
 8  5.25 d
19 12.50 d
 8  5.56 d
 8  7.91 d
 8  6.89 d