Identification: Are all of these cacti?

I bought today some plants, 2 of them i guess are cacti but are they all?could you tell me what they are?

 

1. Senecio rowleyana aka String of Pearls / String of Beads. This is a succulent (not a cactus).
2. Haworthia of some description, again, succulent and not cactus.
3. This is a cactus, and I have no idea.

 

3. Sulcorebutia rauschii

 

thank you very much for the help:D

 

#2 Haworthia fasciata