Level History of Textbook
| Level | Date |
|---|---|
| 15 | 2020-11-25 01:52:31 |
| 14 | 2020-11-25 01:48:56 |
| 13 | 2020-11-25 01:41:15 |
| 12 | 2020-11-25 01:40:07 |
| 11 | 2020-11-25 01:36:59 |
| 10 | 2020-11-24 19:18:19 |
| 9 | 2020-11-24 19:16:13 |
| 8 | 2020-11-24 19:09:13 |
| 7 | 2020-11-24 19:07:27 |
| 6 | 2020-11-24 19:01:31 |
| 5 | 2020-11-24 19:00:14 |
| 4 | 2020-11-24 18:55:42 |
| 3 | 2020-11-24 18:53:52 |
| 2 | 2020-11-24 18:53:19 |