Given the following context:  Odontocetes are known as toothed whales; they have teeth and only one blowhole. They rely on their well-developed sonar to find their way in the water. Toothed whales send out ultrasonic clicks using the melon. Sound waves travel through the water. Upon striking an object in the water, the sound waves bounce back at the whale. These vibrations are received through fatty tissues in the jaw, which is then rerouted into the ear-bone and into the brain where the vibrations are interpreted. All toothed whales are opportunistic, meaning they will eat anything they can fit in their throat because they are unable to chew. These animals rely on their well-developed flippers and tail fin to propel themselves through the water; they swim by moving their fore-flippers and tail fin up and down. Whale ribs loosely articulate with their thoracic vertebrae at the proximal end, but they do not form a rigid rib cage. This adaptation allows the chest to compress during deep dives as opposed to resisting the force of water pressure. Excluding dolphins and porpoises, odontocetes consist of four families: belugas and narwhals (monodontids), sperm whales (physeterids), dwarf and pygmy sperm whales (kogiids), and beaked whales (ziphiids). There are six species, sometimes referred to as "blackfish", that are dolphins commonly misconceived as whales: the killer whale, the melon-headed whale, the pygmy killer whale, the false killer whale, and the two species of pilot whales, all of which are classified under the family Delphinidae (oceanic dolphins).The differences between families of odontocetes include size, feeding adaptations and distribution. Monodontids consist of two species: the beluga and the narwhal. They both reside in the frigid arctic and both have large amounts of blubber. Belugas, being white, hunt in large pods near the surface and around pack ice, their coloration acting as camouflage. Narwhals, being black, hunt in large pods in the aphotic zone, but their underbelly still remains white to remain camouflaged when...  answer the following question:  What animal's underbelly is white to remain camouflaged when something is looking directly up or down at them?
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Answer: Narwhals


Given the following context:  A prologue introduces the Nickelbys, country gentry who enjoy a comfortable life in the Devon countryside until the father dies and leaves his family with no source of income. Nineteen-year-old Nicholas, his mother, and his younger sister, Kate, venture to London to seek help from their wealthy, cold-hearted uncle Ralph, an investor who arranges for Nicholas to be hired as a tutor at Dotheboys Hall in Yorkshire and finds Kate work as a seamstress. Nicholas is horrified to discover his employers, the sadistic Mr and Mrs Squeers, run their boarding school like a prison and physically, verbally, and emotionally abuse their young charges on a regular basis. He eventually rebels and escapes, taking with him the crippled young servant boy Smike. As they journey to London, they stumble upon a theatrical troupe owned and operated by Mr and Mrs Crummles. They cast them in a production of Romeo and Juliet, but despite a successful first night and the couple's invitation to stay, Nicholas is determined to continue their journey to London after hearing that Kate is in trouble. Nicholas discovers his sister has been subjected to humiliating sexual harassment from the lecherous Sir Mulberry Hawk, a client of their uncle, who has encouraged the man to seduce his niece in the hope that she will succumb and thus cement Hawk's business relationship with him. Nicholas confronts Sir Mulberry and his uncle, renouncing the latter.  Nicholas is reunited with his family, who welcome Smike as one of their own, and finds clerical employment with the kindly Cheeryble brothers, who offer him more than double his previous salary. While thus employed, Nicholas makes the acquaintance of Madeline Bray, an artist who financially supports both herself and her tyrannical father, as her father gambled away his fortune and that of his late wife.  answer the following question:  Who escapes and takes a crippled young servant with him?
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Answer: Nicholas


Given the following context:  College student Sarah Foster is found by the police, as she is sleepwalking in her nightgown on the road. Since the suicide of her husband Jonathon, who worked as a novelist, she is suffering from sleep disorder. A few days later, she talks to Dr Cooper, whose student she was, about the sleepwalking and a recurring nightmare, in which she is attacked by an unknown man. Cooper sends her to a therapy in a sleep laboratory. During a walk on a cemetery, Sarah talks about it with her room mate Dawn, who shows a personal interest in her professor Owen. Then an attractive man gets out of a black car and Sarah imagines him being a single. At the evening in the sleep laboratory, Dr. Koslov explains to her that her neuronal activity will be observed during the night. He also introduces her to Dr. Scott White, the director of the lab. It is the man whom Sarah has seen at the cemetery. He tells her, that a student was buried and he was there with a colleague. Sarah confides to him that she loved her husband, but not his work as a novelist. The next morning she wakes up in a different room after a silent, dreamless night. White takes her case. He reports about irregularities in the theta waves and asks her to spend some more nights in the lab. Sarah recognizes that something is wrong. In the lecture hall she questions the statement of her teacher, who thinks that love stories are just a dopamine kick or a bipolar disorder. But she is even more irritated when he addresses her as Miss Wells and a student repeats this name. Also Dawn, her driver's license, her diary and a dedication in her husband's book affirm this surname. Sarah is rejected by Cooper's assistant. In the sleep laboratory Dr Koslov shows her a protocol about her dream in which she is pursued. She denies having dreamed anything, but sees her signature on the form.  answer the following question:  What is the last name of the person who suffers from a sleep disorder?
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Answer:
Foster