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1:13 AM
The question Help on Surjection, Injection, and Bijection asks multiple question in the same post. And it seems that such questions have been already answered.
Some general advice for asking questions on this site: 1) It is better to ask single question in one post. (Your post contains 4 different questions.) 2) It is good to search before asking. (I'd guess that there already are some posts about this on this site.) 3) It is good to explain your terminology. (The last part mention total function. Does this mean that in the first three subquestions you can possible work with partial functions?) See also: How to ask a good question?Martin Sleziak 9 mins ago
Asking multiple questions is discouraged.
Should the question I linked above be closed as too broad? Or would it be more reasonable to pick one of the questions linked in the comments and close as a duplicate? (Although it is duplicate only for one part of the question.)
 

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