They were probably created by the freeware compression utility, 7zip.  I think most other utilities like winzip should be able to extract it.  But if you are already using 7zip, it has to be version 9.2 or later or it won't work.  

Here's one way to proceed:
1. Get 7zip 9.2 or later from downloads.cnet.com (a well-known, long established site by a consumer group that screens stuff to keep out viruses and spyware)
2.  After installation, highlight all the files to be joined and extracted
3. Right click on the highlight and choose 7zip- "Extract Here"
Enjoy.

7zip is a free, open-source program with no ads that does most everything a compression program should, so it's handy to have.

An alternative suggestion is to try PeejeShare (listed above) if it is available to you.  Where I live it's much faster than mediafire, and the file requires no joining or extracting.  The next speediest choice for me would be Sendspace.

Lastly, although I'm a big fan of Hiryuu, I found this episode's translation was not up to their usual standards.  It left me confused and unclear about a lot of stuff in this episode.  The better version so far is, believe it or not, Hadena.  I left some additional comments about the differences under the Hiryuu 8-bit version, if you're interested.