In Kaplansky's Set Theory & Metric Spaces, there is a section containing 19 exercises on Functions. The first two exercises describe one-to-one and onto properties. Can I make a community wiki page in this Q&A style?
It is no longer possible to ask Community Wiki questions: see the StackExchange blog post The Future of Community Wiki:
Community Wiki is primarily for Answers
If we haven’t said this enough already, questions rarely, if ever, need community wiki. What about answers? We removed the ability for users to make a question community wiki, but left the ability for users to make an answer wiki.
Community wiki is for that rare gem of a post that needs true community collaboration. That’s when community wiki shines. If your site is teeming with community wiki posts — particularly in questions — you should consider the above points carefully.
That said, even if it were possible, I think it's a bad idea to ask 19 questions at once (whether in a single post or not). I suggest you ask a single question, learn from it, then ask another question if necessary.