PowerShell $PSVersionTable
Looking at this answer, I don't think you can run 1 & 2 side-by-side without some surgery on the GAC (so it would follow that 1, 2 & 3 don't all co-exist either - only 2 & 3, because 2 & 3 were designed to run side by side). Version 2 was meant to completely replace version 1, AFAICT.
You can not run V1 using the side by side stuff. That was never supported. You CAN run V2 from V3, but not V1.