Misc: In 1961 Experimental reactor kills three in---------- , Idaho.?

Questions

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?

In greek mythology, who hired daedalus to construct the labyrinth?