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: The first eruptions of Nevado del Ruiz occurred about 1.8 million years ago at the beginning of the Pleistocene epoch. Three primary eruption periods in the history of the massif have been identified: ancestral, older and present. During the ancestral period between one million to two million years ago, a complex of large stratovolcanoes was created. Between 1.0 million and 0.8 million years ago, they partially collapsed, forming large (5–10 km wide) calderas. During the older period, which lasted from 0.8 million to 0.2 million years ago, a new complex of large stratovolcanoes developed (including Older Ruiz, Tolima, Quindio, and Santa Isabel). Once again explosive summit calderas formed from 0.2 million to 0.15 million years ago.The present period began about 150,000 years ago and involved the development of the present volcanic edifice through the emplacement of lava domes made of andesite and dacite (igneous rocks) inside older calderas. During the past 11,000 years, Nevado del Ruiz passed through at least 12 eruption stages, which included multiple slope failures (rock avalanches), pyroclastic flows and lahars leading to partial destruction of the summit domes. During the past several thousand years, eruptions of the volcanoes in the Ruiz–Tolima massif have mostly been small, and the pyroclastic flow deposits have been much less voluminous than during the Pleistocene. Since the volcano's earlier eruptions are not recorded, volcanologists have used tephrochronology to date them.During recorded history, eruptions have consisted primarily of a central vent eruption (in the caldera) followed by an explosive eruption, then lahars. Ruiz's earliest identified Holocene eruption was about 6660 BC, and further eruptions occurred in 1245 BC ± 150 years (dated through radiocarbon dating), about 850 BC, 200 BC ± 100 years, 350 AD ± 300 years, 675 AD ± 50 years, in 1350, 1541 (perhaps), 1570, 1595, 1623, 1805, 1826, 1828 (perhaps),[b] 1829, 1831, 1833 (perhaps),[b] 1845, 1916, December 1984 – March 1985, September 1985 – July 1991, and possibly in April 1994.[b] Many of these eruptions involved a central vent eruption, a flank vent eruption, and a phreatic (steam) explosion. Ruiz is the second-most active volcano in Colombia after Galeras.
What partially collapsed, forming large (5–10 km wide) calderas?

Passage: The company, retaining the title "Sadler's Wells Opera", opened at the Coliseum on 21 August 1968, with a new production of Mozart's Don Giovanni, directed by Sir John Gielgud. Though this production was not well received, the company rapidly established itself with a succession of highly praised productions of other works. Arlen died in January 1972, and was succeeded as managing director by Lord Harewood.The success of the 1968 Mastersingers was followed in the 1970s by the company's first Ring cycle, conducted by Goodall, with a new translation by Andrew Porter and designs by Ralph Koltai.  The cast included Norman Bailey, Rita Hunter and Alberto Remedios. In Harewood's view, among the highlights of the first ten years at the Coliseum were the Ring, Prokofiev's War and Peace, and Richard Strauss's Salome and Der Rosenkavalier.
The company's musical director from 1970 to 1977 was Charles Mackerras. Harewood praised his exceptional versatility, with a range "from The House of the Dead to Patience." Among the operas he conducted for the company were Handel's Julius Caesar starring Janet Baker and Valerie Masterson; five Janáček operas; The Marriage of Figaro with pioneering use of 18th century performing style; Massenet's Werther; Donizetti's Mary Stuart with Baker; and Sullivan's Patience. The company took the production of the last to the Vienna Festival in 1975, along with Britten's Gloriana. Sir Charles Groves succeeded Mackerras as musical director from 1978 to 1979, but Groves was unwell and unhappy during his brief tenure. Starting in 1979, Mark Elder succeeded Groves in the post, and described Groves "immensely encouraging and supportive".A long-standing concern of Arlen and then Harewood was the need to change the company's name to reflect the fact that it was no longer based at Sadler's Wells theatre. Byam Shaw commented "The one major setback the Sadler's Wells Opera Company suffered from its transplant was that unheeding taxi drivers kept on taking their patrons up to Rosebery Avenue".Harewood considered it an elementary rule that "you must not carry the name of one theatre if you are playing in another one." Covent Garden, protective of its status, objected to the suggestion that the Sadler's Wells company should be called "The British National Opera" or "The National Opera", although neither Scottish Opera nor the Welsh National Opera opposed such a change. Eventually the British government decided the matter, and the title "English National Opera" was approved. The company's board adopted the new name in November 1974. In 1977, in response to demand for more opera productions in English provincial cities, a second company was established. It was based at Leeds in northern England, and was known as ENO North. Under Harewood's guidance, it flourished, and in 1981 it became an independent company, Opera North.
What name did the company that was  titled "Sadler's Wells Opera" eventually change its name to?

Passage: At the 2001 UK census, Brownhills ward had a population of 12,637, and a population density of 17.45 persons per hectare.Of the town's 5,151 households, 40.7% were married couples living together, 10.4% were cohabiting couples and 10.2% were lone parents. 25.9% of all households were made up of individuals and 12.8% had someone living alone at pensionable age. 31.8% of households included children aged under 16 or a person aged 16 to 18 who was in full-time education. The average household size was 2.5.The ethnicity of the town was 97.4% white, 0.6% mixed race, 1.2% Asian, 0.5% black and 0.3% Chinese or other. The country of birth of residents was 97.8% United Kingdom, 0.4% Republic of Ireland, 0.2% Germany, 0.2% other Western European countries, 0.2% Eastern Europe, 0.2% Africa, 0.3% Far East, 0.4% South Asia, <0.1% Middle East, 0.2% North America and <0.1% Oceania. Religion was recorded as 79.6% Christian, 0.6% Muslim, 0.2% Hindu, 0.1% Buddhist, 0.1% Jewish and 0.3% Sikh. 12.5% were recorded as having no religion, 0.1% had an alternative religion and 6.5% did not state their religion.For every 100 females, there were 98.04 males. The age distribution was 6.6% aged 0–4 years, 15.0% aged 5–15 years, 4.2% aged 16–19 years, 36.3% aged 20–44 years, 23.6% aged 45–64 years and 14.1% aged 65 years and over. The mean population age was 37.5, lower than the national average of 38.6.The economic activity of residents aged 16–74 was 43.2% in full-time employment, 12.3% in part-time employment, 6.1% self-employed, 3.8% unemployed, 1.3% students with jobs, 2.3% students without jobs, 13.5% retired, 7.3% looking after home or family, 6.9% permanently sick or disabled and 3.3% economically inactive for other reasons. The percentage of people in full-time employment was significantly higher than the 39.1% average for the whole of the Walsall district. Of the town's residents aged 16–74, 8.5% had a higher education qualification or the equivalent, compared with 19.9% nationwide. According to Office for National Statistics estimates, during the period of April 2001 to March 2002 the average gross weekly income of households in the Brownhills area was £460 (£23,920 per year).

What percentage of residents in the town with a population of 12,637 between the ages of 16-74 had a higher education?