| Value | Category | Cases | |
|---|---|---|---|
| 1 | Very difficult | 2 |
2.1%
|
| 2 | Difficult | 9 |
9.6%
|
| 3 | Normal | 33 |
35.1%
|
| 4 | Easy | 38 |
40.4%
|
| 5 | Very easy | 12 |
12.8%
|
| 11 | .F | 419 |