Misc: what is the element for the symbol Nd?

Questions

In greek mythology, who did oedipus marry?

In greek mythology, who did zeus place in the heavens as the constellation ursa major?

In greek mythology, who had a ship with a beam hewn from the 'speaking oaks of dodona'?

In greek mythology, who had nine heads?

In greek mythology, who helped theseus escape the labyrinth?