00:02
0
student
00:02 
00:01
0
13:33
0
05:37:36
5
03:25
0
13:12
3
08:04
0
03:21
0
10:42
1
03:27
0
00:10
2
05:15
1
00:01
3
04:54
0
05:39
0
00:08
0
00:08
3
10:41:40
0