Which of the following is necessarily true for a functionf:x~y? (a) if s is injective, then there exists g:yx such that s(9(u)) = y for all yey () iffis surject

Which of the following is necessarily true for a functionf:x~Y? (a) If s is injective, then there exists g:YX such that s(9(u)) = y for all yEY () Iffis surjective, then there.exists g:Y>X such that f(g(u) =y for all yeY (c) is injective and Yis countable then Xis finite ()1ffis surjective and X is uncountable then Yis countably infinite