01:05
0
student
01:05 
03:21
3
01:42
1
00:57
10
04:36
2
04:11
2
07:03
4
00:40
0
01:33
0
02:27
1
01:00
0
01:17
0
01:09
0
02:12
0
00:54
0
01:59
0
02:12
0
01:51
0
00:59
5
00:56
0
00:49
0
01:07
0
00:30
1
01:21
3
01:14
0
02:25
0
02:29
0
02:00
1
04:15
0
01:08
0