: You only need to right-click on Part 1 and select "Extract." Your extraction software (like WinRAR or 7-Zip) will automatically pull the data from Part 2 and any subsequent parts to reconstruct the original file.
If you are looking for a description or a "piece" of writing to accompany this file for a blog or forum post, you might use something like this: 13Full.part2.rar
: You cannot "open" or "play" part 2 by itself. You must have all parts of the archive (Part 1, Part 2, etc.) in the same folder. : You only need to right-click on Part 1 and select "Extract