Incorrect numbering of exercises or missing exercises

**Description:**
Incorrect numbering of exercises or missing exercises.
If you go over the numbers of all the exercises, these are the exercises / numbers that are missing:
109, 113, 123, 129, 130, 133, 136, 138, 139, 142, 149, 151, 152, 154, 155, 159, 160, 163-165, 167, 169, 170, 172, 174-176, 178-194