The following text is for questions 18 to 20.

    Hercules had a complicated family tree. According to the legend, his father was Zeus, ruler of all the gods on Mount Olympus and all the mortals on earth, and his mother was Alcmene, the granddaughter of the hero Perseus.

    Hercules had enemies even before he was born. When Zeus' wife Hera heard that her husband's mistress was pregnant, she flew into a jealous rage. First, she used her supernatural powers to prevent the baby Hercules from becoming the ruler of Mycenae. (Though Zeus had declared that his son would inherit the Mycenaean Kingdom, Hera's meddling meant that another baby boy, the feeble Eurystheus, became its leader instead). Then, after Hercules was born, there were two snakes on his crib trying to strangle him. The infant Hercules was unusually strong and fearless, however, and he strangled the snakes before they could strangle him.

    When Hera's stepson was a young adult, she cast a kind of spell on him that drove him temporarily insane. Guilty and heartbroken, Hercules tracked down Apollo, the god of truth and healing (and another of Zeus' sons), and begged to be punished for what he had done.

(Adopted from: https://www.history.com/topics/ancient-history/hercules (September 19, 2019))

Who was Hera?