| Value |
Category |
| 0 |
|
| 1 |
it is easy |
| 2 |
it is difficult |
| 3 |
it is very difficult |
| 4 |
impossible |
| 5 |
I donot know |
| 6 |
I never asked |
| 7 |
other |
Warning: these figures indicate the number of cases found in the data file. They cannot be interpreted as summary statistics of the population of interest.