What is the tray made of?
The tray is made of plastic.
    src        edge_attr  dst
0     0             with    4
1     0  to the right of   10
2     0  to the right of    1
3     0            above    3
4     0  to the right of   11
5     1   to the left of    3
6     1   to the left of    0
7     1   to the left of    5
8     1   to the left of    4
9     1               in   11
10    2            above   14
11    3  to the right of   11
12    3  to the right of   10
13    3  to the right of    8
14    3  to the right of    1
15    3            under    0
16    4               on    3
17    4               on    0
18    4             with   15
19    4  to the right of   10
20    4  to the right of    1
21    4  to the right of   11
22    5  to the right of    1
23    5  to the right of   11
24    5  to the right of   10
25    6               on    2
26    6  to the right of   14
27    8   to the left of    3
28   10   to the left of    4
29   10               on    1
30   10   to the left of    5
31   10   to the left of   15
32   10   to the left of    0
33   10   to the left of    3
34   11   to the left of    4
35   11   to the left of    3
36   11   to the left of    0
37   11   to the left of   15
38   11   to the left of    5
39   12               on    2
40   12  to the right of   14
41   13               on    2
42   13  to the right of   14
43   14   to the left of   12
44   14            under    2
45   14   to the left of   13
46   14   to the left of    6
47   15  to the right of   10
48   15  to the right of   11
49   15               on    4