what are the order of the difficulty levels of the gerdig ufo?

http://www.geocities.com/jaapsch/puzzles/gerdig.htm

i think easy level is level one, but the others...?

1. One sphere.
2. Two opposite spheres.
3. Four spheres.
4. Two spheres at 90 degrees to each other.
5. Three spheres.

thanks

The only one I couldn't do completely intuitively was three spheres. My suggestion is to take your UFO and set it to three spheres immediately, and just leave it there. Marketing it with the resettability at all was a mistake - most people won't manage to get it back together again, and only one of the settings is of real interest anyway.

thanks for help

then 3 spheres...