What color is the helmet that is made of plastic?
The helmet is gray.
    src        edge_attr  dst
0     3             near   11
1     3  to the right of   10
2     3  to the right of    8
3     3  to the right of    4
4     3             near    7
5     3  to the right of    7
6     4   to the left of    3
7     4   to the left of    8
8     6   to the left of    9
9     7          wearing    0
10    7   to the left of    8
11    7   to the left of    3
12    7             near    3
13    8               on   11
14    8  to the right of    7
15    8  to the right of   10
16    8   to the left of    3
17    8  to the right of    4
18    9  to the right of    6
19   10   to the left of    8
20   10   to the left of    3
21   11             near    3