Q: In this task, you're given passages that contain mentions of names of people, places, or things. Some of these mentions refer to the same person, place, or thing. Your job is to write questions that evaluate one's understanding of such references. Good questions are expected to link pronouns (she, her, him, his, their, etc.) or other mentions to people, places, or things to which they may refer. Do not ask questions that can be answered correctly without understanding the paragraph or having multiple answers. Avoid questions that do not link phrases referring to the same entity. For each of your questions, the answer should be one or more phrases in the paragraph, and it should be unambiguous.
Passage: When charter-boat skipper Jack O'Conner finds a gold Spanish dollar off the Florida Keys, he decides to go in search of a legendary hoard of Spanish doubloons sunk during the "Hundred Years Storm" of 1780. For, as Jack's friend Cap'n Billau reveals, the coin bears a clue to the treasure's whereabouts – one of four islands etched by the infamous pirate, Jacques Un-Oeil upon the original doubloon. At Billau's urging, Jack tracks down the two beautiful women who unknowingly hold the remaining clues.
Streetwise Sandy Sequoia's piece of eight came from her murdered drug dealer boyfriend in Miami. And lonely-heart Portia Pennington inherited her coin from her merchant tycoon grandfather, who died at sea in the "Hundred Years Storm" of 1893, while hunting for the lost gold.
Jack convinces the girls to go in search of the pirate treasure with him. But first, the two must learn to crew his 76' schooner; and then, all three adventurers must learn to trust one another, if they expect to navigate the treacheries of love and the unpredictable Caribbean.
As Jack introduces the girls to life at sea, he starts to fall in love with Sandy. All seems to be going well, until Jack discovers Sandy with drugs on his boat – a kilo of her dead boyfriend's cocaine (which she has steadily been using since coming aboard). He has Portia dump the coke overboard; and while Sandy wrestles to overcome her addiction, Jack turns his attentions to Portia.
When Sandy and Portia realize that Jack has seduced each of them in turn and convinced each to reveal to him the name of the island on her coin, they turn on him. Feeling betrayed and realizing that they no longer need Jack in order to sail the boat or find the gold, they maroon him on a small island and go after the sunken treasure themselves.
A:
What is the last name of the person who is friends with Cap'n Billau?