You need to include the names of the Operating Systems if you want a answer, because there are hundreds of different Linux variations.
Redhat and Mandrake are not versions of any operating system. Both are itself standalone Linux operating systems.
there is no "linux operating system". linux is merely a kernel that operating systems can be built upon, of which there are dozens if not hundreds
Operating systems are developed by 3 major companies. Microsoft makes Windows, Macintosh makes macs, and Linux makes Linux operatin systems. There are a variety of versions of each OS.
Two operating systems are; Windows, and Linux.
Linux, Windows, OSX
Some different operating systems such as different versions of Linux may be downloaded for free through Ubuntu, Cnet or Linux. Other systems such as those for Microsoft or Apple must be purchased and then downloaded via the vendors own portal.
There are no "joined" Linux and Windows operating systems, so there is no name for them.
"Distros", or distributions.
You need different versions to run it on different Operating Systems. I think you can get it for Windows, Macintosh, and Linux.
No.
There are a few operating systems. Typical examples for home PCs include: Windows, in it's many versions. Mac OS (like OS X). There are many versions of Linux, like Debian, Red hat, and Slackware, Suse and FreeBSD Other operating systems exist for things like mainframes Unix (on which Linux is based) is one. Many other proprietary systems exist as well. A more in depth treatment can be found here:
They are all Linux-type operating systems.