Is there a function f : N → N such that, for all k ∈ N, every graph of minimum degree at least f (k) is k-connected?

Let h(g₁, 92) be a continuous function through a nonempty, closed and bounded set S. Are these conditions necessary, sufficient, necessary and sufficient or neither necessary nor sufficient conditions to ensure that there exists points (a, b) and (c, d) in S where h has a minimum and a maximum value, respectively? Necessary and sufficient Sufficient, but not necessary Neither necessary nor sufficient Necessary, but not sufficient None of the above No answer

3

Prove that A does not have a maximum (or greatest element).