| Value | Category | Cases | |
|---|---|---|---|
| 1 | Very easy | 974 |
44.3%
|
| 2 | Easy | 809 |
36.8%
|
| 3 | Difficult | 319 |
14.5%
|
| 4 | Very difficult | 47 |
2.1%
|
| 9 | Don't know | 49 |
2.2%
|