Using a Mac OSX 10.11.5 with Adobe Acrobat reader DC. Received a very large file and need to create a subset of that file (i.e. 13 pages, not 21). How can I do that?
Not possible with Reader. You need the full Acrobat for that.
Adobe Acrobat reader DC is not for editing matter, it is just a reader (a viewer). If you want to do editing purposes you have to get Adobe Acrobat Pro DC.