instruction:
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.
question:
Passage: A tsunami is an unusual form of wave caused by an infrequent powerful event such as an underwater earthquake or landslide, a meteorite impact, a volcanic eruption or a collapse of land into the sea. These events can temporarily lift or lower the surface of the sea in the affected area, usually by a few feet. The potential energy of the displaced seawater is turned into kinetic energy, creating a shallow wave, a tsunami, radiating outwards at a velocity proportional to the square root of the depth of the water and which therefore travels much faster in the open ocean than on a continental shelf. In the deep open sea, tsunamis have wavelengths of around 80 to 300 miles (130 to 480 km), travel at speeds of over 600 miles per hour (970 km/hr) and usually have a height of less than three feet, so they often pass unnoticed at this stage. In contrast, ocean surface waves caused by winds have wavelengths of a few hundred feet, travel at up to 65 miles per hour (105 km/h) and are up to 45 feet (14 metres) high.A trigger event on the continental shelf may cause a local tsunami on the land side and a distant tsunami that travels out across the ocean. The energy of the wave is dissipated only gradually, but is spread out over the wave front, so as the wave radiates away from the source, the front gets longer and the average energy reduces, so distant shores will, on average, be hit by weaker waves. However, as the speed of the wave is controlled by the water depth, it does not travel at the same speed in all directions, and this affects the direction of the wave front - an effect known as refraction - which can focus the strength of the advancing tsunami on some areas and weaken it in others according to undersea topography.
As a tsunami moves into shallower water its speed decreases, its wavelength shortens and its amplitude increases enormously, behaving in the same way as a wind-generated wave in shallow water, but on a vastly greater scale.  Either the trough or the crest of a tsunami can arrive at the coast first. In the former case, the sea draws back and leaves subtidal areas close to the shore exposed which provides a useful warning for people on land. When the crest arrives, it does not usually break but rushes inland, flooding all in its path. Much of the destruction may be caused by the flood water draining back into the sea after the tsunami has struck, dragging debris and people with it. Often several tsunami are caused by a single geological event and arrive at intervals of between eight minutes and two hours. The first wave to arrive on shore may not be the biggest or most destructive.  Occasionally, a tsunami may transform into a bore, typically in a shallow bay or an estuary.
answer:
What two types of tsunami's can a trigger event on the continental shelf cause?


question:
Passage: In 1990, Zappa was diagnosed with terminal prostate cancer. The disease had been developing unnoticed for ten years and was considered inoperable. After the diagnosis, Zappa devoted most of his energy to modern orchestral and Synclavier works. Shortly before his death in 1993 he completed Civilization Phaze III, a major Synclavier work which he had begun in the 1980s.In 1991, Zappa was chosen to be one of four featured composers at the Frankfurt Festival in 1992 (the others were John Cage, Karlheinz Stockhausen, and Alexander Knaifel). Zappa was approached by the German chamber ensemble Ensemble Modern which was interested in playing his music for the event. Although ill, he invited them to Los Angeles for rehearsals of new compositions and new arrangements of older material. Zappa also got along with the musicians, and the concerts in Germany and Austria were set up for later in the year. Zappa also performed in 1991 in Prague, claiming that "was the first time that he had a reason to play his guitar in 3 years", and that that moment was just "the beginning of a new country", and asked the public to "try to keep your country unique, do not change it into something else".In September 1992, the concerts went ahead as scheduled but Zappa could only appear at two in Frankfurt due to illness. At the first concert, he conducted the opening "Overture", and the final "G-Spot Tornado" as well as the theatrical "Food Gathering in Post-Industrial America, 1992" and "Welcome to the United States" (the remainder of the program was conducted by the ensemble's regular conductor Peter Rundel). Zappa received a 20-minute ovation. G-Spot Tornado was performed with Canadian dancer Louise Lecavalier. It was his last professional public appearance as the cancer was spreading to such an extent that he was in too much pain to enjoy an event that he otherwise found "exhilarating". Recordings from the concerts appeared on The Yellow Shark (1993), Zappa's last release during his lifetime, and some material from studio rehearsals appeared on the posthumous Everything Is Healing Nicely (1999).
answer:
In what city was Zappa's last professional public appearance?


question:
Passage: In 1933, Lewis Tater, an aspiring novelist who harbors dreams of becoming the next Zane Grey, decides to leave his family home in Iowa to go to the University of Titan in Nevada so he can soak up the western atmosphere. He arrives to find that there is no university, only a mail order correspondence course scam run by two crooks out of the local hotel. He tries to spend the night at the hotel, but is attacked by one of the men in an attempted robbery. He escapes his attacker, grabs his suitcase, and steals their car to get away, but after awhile   it runs out of gas. He looks in the car trunk, and finds a toolbox containing a revolver and ammunition. Afraid the two crooks are still in pursuit of him, he takes the tool box and his suitcase and walks off into the desert. 
Wandering and exhausted, the next morning he happens upon a threadbare film-unit from Tumbleweed Productions grinding out a "B" western. Later that day, he catches a lift with the cowboy actors to Los Angeles. After applying for work at Tumbleweed, he is referred by crusty old extra Howard Pike to the Rio, a western-themed restaurant. While washing dishes at the Rio, he is called by Tumbleweed, where Howard mentors him to be an actor. After proving himself as a stuntman, unit manager Kessler offers him a speaking role. Tater then falls in love with spunky script girl Miss Trout. Meanwhile, the crooks trace him to Los Angeles to retrieve the safe-box containing their money that was in the car stolen by Lewis.
answer:
What is the last name of the person who the crooks trace to Los Angeles?