7-Zip is open-source and widely vetted by security experts.
Yes, if the file is too large for a post, you can create a multi-part archive (e.g., jpdc16.7z.001 , jpdc16.7z.002 ) by specifying a volume size like -v100m in the command line.
Creating a complete post for a file named jpdc16.7z typically refers to generating a distribution post (often for forums, social media, or file-sharing sites) that provides all the necessary details for a recipient to understand and use the archive. Use this template if you are sharing the file with others.