31:20 68
students
31:20 
19:01 5
13:44 3
18:38 5
41:53 4
30:23 3
45:29 20
37:37 12
40:26 5
37:21 14
15:00 4
45:23 7
45:26 7
13:37 41
12:08 32
08:22 43
42:11 35
00:56 55
08:58 37
23:32 39
