Who is wearing a knee pad?
The biker is wearing a knee pad.
    src        edge_attr  dst
0     0   to the left of   18
1     0   to the left of    5
2     0   to the left of   15
3     0   to the left of   13
4     1  to the right of   16
5     1  to the right of    9
6     1  to the right of    5
7     1  to the right of   15
8     2   to the left of   12
9     3  to the right of    9
10    3  to the right of    5
11    4   to the left of   12
12    5  to the right of   16
13    5  to the right of    0
14    5   to the left of   18
15    5   to the left of    1
16    5   to the left of    3
17    9               on    8
18    9   to the left of   12
19    9          wearing    4
20    9   to the left of    3
21    9   to the left of    1
22    9   to the left of   18
23   12  to the right of    9
24   12  to the right of    2
25   12  to the right of    4
26   12  to the right of   17
27   13  to the right of    0
28   15  to the right of    0
29   15   to the left of    1
30   15   to the left of   18
31   16   to the left of   18
32   16   to the left of    1
33   16   to the left of    5
34   17   to the left of   12
35   18  to the right of   15
36   18  to the right of   16
37   18  to the right of    9
38   18  to the right of    5
39   18  to the right of    0