In this task, you're expected to write answers to questions involving multiple references to the same entity. The answer to the question should be unambiguous and a phrase in the paragraph. Most questions can have only one correct answer.

Example Input: Passage: Nannerl herself was an   apt pupil, no less quick to learn than her brother, and was playing the keyboard with striking virtuosity by the time she was eleven. In that year, 1762, Leopold brought the children to Munich to play before Maximilian III Joseph, Elector of Bavaria. Leopold then took the entire family to Vienna, on a trip that lasted for three months. He had secured invitations from several noble patrons, and within three days of arriving the children were playing at the palace of Count Collalto. Among those present was the Viennese Treasury councillor and future prime minister Karl von Zinzendorf, who noted in his diary that "a little boy, said to be only five-and-a-half years old [Wolfgang was actually nearly seven], played the harpsichord". After an appearance before the Imperial Vice-Chancellor, the Mozarts were invited to the royal court, where the Empress Maria Theresa tested Wolfgang's abilities by requiring him to play with the keyboard covered. During this court visit Wolfgang met the Archduchess Maria Antonia, the future Queen Marie Antoinette of France, who was two months his senior. Mozart's biographer Eric Blom recounts an anecdote of how the Archduchess helped Wolfgang when he slipped on the polished floor; she is supposed to have received a proposal of marriage in return.As the Mozarts began to be noticed by the Viennese aristocracy, they were often required to give several performances during a single day. They were well rewarded for this activity—at the end of their first hectic week in Vienna, Leopold was able to send home the equivalent of more than two years' salary. Their schedule was interrupted when Wolfgang fell ill with scarlet fever, and their former momentum was not regained. Nevertheless, the visit left Leopold eager to pursue further opportunities for social and financial success. On their return to Salzburg, Wolfgang played the harpsichord and violin at a birthday concert for the archbishop, to the evident astonishment of those present. 
Question: Who played the keyboard with striking virtuosity?
Example Output: Wolfgang.

Example Input: Passage: Transportation in Oklahoma is generated by an anchor system of Interstate Highways, inter-city rail lines, airports, inland ports, and mass transit networks. Situated along an integral point in the United States Interstate network, Oklahoma contains three primary Interstate highways and four auxiliary Interstate Highways. In Oklahoma City, Interstate 35 intersects with Interstate 44 and Interstate 40, forming one of the most important intersections along the United States highway system.More than 12,000 miles (19,000 km) of roads make up the state's major highway skeleton, including state-operated highways, ten turnpikes or major toll roads, and the longest drivable stretch of Route 66 in the nation. In 2008, Interstate 44 in Oklahoma City was Oklahoma's busiest highway, with a daily traffic volume of 123,300 cars. In 2010, the state had the nation's third-highest number of bridges classified as structurally deficient, with nearly 5,212 bridges in disrepair, including 235 National Highway System Bridges.Oklahoma's largest commercial airport is Will Rogers World Airport in Oklahoma City, averaging a yearly passenger count of more than 3.5 million (1.7 million boardings) in 2010. Tulsa International Airport, the state's second-largest commercial airport, served more than 1.3 million boardings in 2010. Between the two, six airlines operate in Oklahoma. In terms of traffic, R. L. Jones Jr. (Riverside) Airport in Tulsa is the state's busiest airport, with 335,826 takeoffs and landings in 2008. Oklahoma has over 150 public-use airports.Oklahoma is connected to the nation's rail network via Amtrak's Heartland Flyer, its only regional passenger rail line. It currently stretches from Oklahoma City to Fort Worth, Texas, though lawmakers began seeking funding in early 2007 to connect the Heartland Flyer to Tulsa.Two inland ports on rivers serve Oklahoma: the Port of Muskogee and the Tulsa Port of Catoosa. The state's only port handling international cargo, the Tulsa Port of Catoosa is the most inland ocean-going port in the nation and ships over two million tons of cargo each year. Both ports are on the McClellan–Kerr Arkansas River Navigation System, which connects barge traffic from Tulsa and Muskogee to the Mississippi River via the Verdigris and Arkansas rivers, contributing to one of the busiest waterways in the world. 
Question: What is the name of Amtrack's rail line that currently stretches from Oklahoma City to Fort Worth Texas?
Example Output: Heartland Flyer.

Example Input: Passage: On 21 January 1818, Friedrich married Caroline Bommer, the twenty-five-year-old daughter of a dyer from Dresden. The couple had three children, with their first, Emma, arriving in 1820.  Physiologist and painter Carl Gustav Carus notes in his biographical essays that marriage did not impact significantly on either Friedrich's life or personality, yet his canvasses from this period, including Chalk Cliffs on Rügen—painted after his honeymoon—display a new sense of levity, while his palette is brighter and less austere. Human figures appear with increasing frequency in the paintings of this period, which Siegel interprets as a reflection that "the importance of human life, particularly his family, now occupies his thoughts more and more, and his friends, his wife, and his townspeople appear as frequent subjects in his art."Around this time, he found support from two sources in Russia. In 1820, the Grand Duke Nikolai Pavlovich, at the behest of his wife Alexandra Feodorovna, visited Friedrich's studio and returned to Saint Petersburg with a number of his paintings, an exchange that began a patronage that continued for many years. Not long thereafter, the poet Vasily Zhukovsky, tutor to Alexander II, met Friedrich in 1821 and found in him a kindred spirit. For decades Zhukovsky helped Friedrich both by purchasing his work himself and by recommending his art to the royal family; his assistance toward the end of Friedrich's career proved invaluable to the ailing and impoverished artist. Zhukovsky remarked that his friend's paintings "please us by their precision, each of them awakening a memory in our mind."Friedrich was acquainted with Philipp Otto Runge, another leading German painter of the Romantic period. He was also a friend of Georg Friedrich Kersting, and painted him at work in his unadorned studio, and of the Norwegian painter Johan Christian Clausen Dahl (1788–1857). Dahl was close to Friedrich during the artist's final years, and he expressed dismay that to the art-buying public, Friedrich's pictures were only "curiosities". While the poet Zhukovsky appreciated Friedrich's psychological themes, Dahl praised the descriptive quality of Friedrich's landscapes, commenting that "artists and connoisseurs saw in Friedrich's art only a kind of mystic, because they themselves were only looking out for the mystic... They did not see Friedrich's faithful and conscientious study of nature in everything he represented".During this period Friedrich frequently sketched memorial monuments and sculptures for mausoleums, reflecting his obsession with death and the afterlife; he even created designs for some of the funerary art in Dresden's cemeteries. Some of these works were lost in the fire that destroyed Munich's Glass Palace (1931) and later in the 1945 bombing of Dresden. 
Question: What is the full name of the person who expressed dismay that to the art-buying public, Friedrich's pictures were only "curiosities"?
Example Output:
Johan Christian Clausen Dahl.