Which color are the skateboard wheels?
The wheels are green.
    src        edge_attr  dst
0     0   to the left of    2
1     0   to the left of    4
2     1      standing on   12
3     1   to the left of    4
4     2        parked by    5
5     2        parked on   14
6     2  to the right of    0
7     2  to the right of    5
8     2   to the left of   10
9     2   to the left of    4
10    4      standing on   11
11    4  to the right of    8
12    4  to the right of    2
13    4  to the right of    0
14    4  to the right of   17
15    4  to the right of   12
16    4  to the right of    1
17    4  to the right of   15
18    4  to the right of   16
19    4  to the right of    5
20    5   to the left of    2
21    5   to the left of    7
22    5   to the left of    4
23    7   to the left of   10
24    7   to the left of    9
25    7  to the right of    5
26    7  to the right of   12
27    8   to the left of    4
28    9  to the right of   17
29    9  to the right of    7
30   10  to the right of    2
31   10  to the right of    7
32   10  to the right of   17
33   10      standing on   11
34   12   to the left of    7
35   12   to the left of    4
36   12   to the left of   17
37   12       going down   14
38   15   to the left of    4
39   16   to the left of    4
40   17  to the right of   12
41   17   to the left of   10
42   17   to the left of    9
43   17   to the left of    4