In this task, you're given a passage, further information available on a particular linked term from the statement, and an answer term. Your job is to generate a question that can use the information provided to obtain the given answer. You should use the information on both passage and link information to create the question. Note that the answer to the question should be exactly the given answer, and if the answer is none, the answer to the question shouldn't be obtainable from the passage or linked information.
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Question: Passage: In 1809, Walter Coffin sunk the first coal pit in the Rhondda, further up the valley in Dinas, but a lack of a transportation network greatly affected the profitability of coal mining as an industry in the region. Coffin tackled this problem by constructing a one-mile tramline which connected his mines in Dinas to a tramline built by Dr. Richard Griffiths at Denia (Pontypridd), which linked to a private canal that joined onto the Glamorganshire Canal at Treforest. Coffins tramline followed the southern bank of the River Rhondda and ran through Porth. The existence of the tramline made the development of the Porth and Cymmer region far more attractive, and by the middle of the 19th century there was an impetus to expand coal mining in the area. In 1841 Richard Lewis joined Coffin in trying to exploit the region with his level built at Cymmer. This resulted in the construction of around fifty miners' cottages, several of which were located in Porth. In 1844 Lewis Edwards of Newport and George Gethin of Penygraig opened a small level at Nyth-bran on the eastern borders of Porth, the villages' first coal mine. This was followed in 1845 by the sinking of the Porth Colliery by David James of Merthyr, the success of which saw him build the Llwyncelyn Colliery in 1951, also in Porth. By 1850 the Taff Vale Railway had been extended to Cymmer replacing the tramline, allowing direct access between the lower Rhondda and the ports of Cardiff.
Link Information: It was opened in stages in 1840 and 1841. Answer: 10

Answer: How long had the Taff Vale Railway been in existence the year it was extended to Cymmer?

Question: Passage: The Lookout Mountain Incline Railway is a inclined plane funicular railway leading to the top of Lookout Mountain from the historic St. Elmo neighborhood of Chattanooga, Tennessee. Passengers are transported from St. Elmo's Station at the base, to Point Park at the mountain summit, which overlooks the city and the Tennessee River. It is just a short drive to three of Chattanooga's main tourist attractions, Ruby Falls, Cavern Castle, and Rock City. The railway is approximately in length (single-track except for a short two-track passing loop at the midway point, allowing operation of two cars at one time). It has a maximum grade of 72.7%, making it one of the world's steepest passenger railways. It obtained Historic Mechanical Engineering Landmark status in 1991. The cable system for the cars was made by the Otis Elevator Company.
Link Information: none Answer: none

Answer: How many miles from Chattanooga, Tennessee does it take to travel to Lookout Mountain by railway?

Question: Passage: Irene was daughter of despotes Theodore Komnenos Doukas, ruler of Epirus, and Maria Petraliphaina (sister of the sebastokrator John Petraliphas). In 1230 Irene and her family were captured by the troops of tsar Ivan Asen II of Bulgaria in the battle of Klokotnitsa and they were taken in Tarnovo, where Irene grew up in the Palace. Irene became known for her beauty and the widowed tsar fell in love with her. They married in 1237. According to a Byzantine author, Ivan Asen II loved Irene "no less than Antony loved Cleopatra", and she may have been his mistress for some years before their marriage in 1237. By marrying Irene, Ivan Asen II would have broken church canons, as his daughter, Maria Asanina Komnena, from his marriage to Anna (Anisia) was married to Irene's uncle, Manuel of Thessalonica. There is some evidence that the Bulgarian church opposed the marriage and that a patriarch (called either Spiridon or Vissarion) was deposed or executed by the irate tsar.
Link Information: Ivan Asen II, also known as John Asen II or John Asan II (, ; 1190s May/June 1241) Answer: 40

Answer:
At what age was Ivan Asen II of Bulgaria when his troops captured Irene and her family?