Not necessarily printed on the disk... I have two copies with no indication of version on the disk that are both 2.01. One of these I opened myself, the other was bought already open. So I can pretty much rule out a possible disk swap.
You can tell by opening the Readme File on the disks root directory.
I was told that the 1.0 version didn't contain an editor also, and that is how you can tell it was 1.0. The levels are the same, but they added content to the disk.
Also, these disks are in cases with two different booklets. One booklet has "Free Inside" red circle and the other booklet has the "*These levels were independently created by 3rd parties..."
One Booklet is 6-96 the other is 10-96.
MrBlackCat