Question: One wave of the population boom ended abruptly in the mid-1980s, as oil prices fell precipitously. The space industry also suffered in 1986 after the Space Shuttle Challenger disintegrated shortly after launch. There was a cutback in some activities for a period. In the late 1980s, the city's economy suffered from the nationwide recession. After the early 1990s recession, Houston made efforts to diversify its economy by focusing on aerospace and health care/biotechnology, and reduced its dependence on the petroleum industry. Since the increase of oil prices in the 2000s, the petroleum industry has again increased its share of the local economy.
Is there an answer to this question: What did Houston focus on after the 1990s recession to improve its economy?

Answer: aerospace and health care

Question: Current manager, Roberto Martinez, is the fourteenth permanent holder of the position since it was established in 1939. There have also been four caretaker managers, and before 1939 the team was selected by either the club secretary or by committee. The club's longest-serving manager has been Harry Catterick, who was in charge of the team from 196173, taking in 594 first team matches. The Everton manager to win most domestic and international trophies is Howard Kendall, who won two Division One championships, the 1984 FA Cup, the 1984 UEFA Cup Winners' Cup, and three Charity Shields.
Is there an answer to this question: Who was the Everton FC team's longest serving manager?

Answer: Harry Catterick

Question: John XXIII was an advocate for human rights which included the unborn and the elderly. He wrote about human rights in his Pacem in terris. He wrote, "Man has the right to live. He has the right to bodily integrity and to the means necessary for the proper development of life, particularly food, clothing, shelter, medical care, rest, and, finally, the necessary social services. In consequence, he has the right to be looked after in the event of ill health; disability stemming from his work; widowhood; old age; enforced unemployment; or whenever through no fault of his own he is deprived of the means of livelihood."
Is there an answer to this question: What did widows advocate for?

Answer: unanswerable

Question: Data compression can be viewed as a special case of data differencing: Data differencing consists of producing a difference given a source and a target, with patching producing a target given a source and a difference, while data compression consists of producing a compressed file given a target, and decompression consists of producing a target given only a compressed file. Thus, one can consider data compression as data differencing with empty source data, the compressed file corresponding to a "difference from nothing." This is the same as considering absolute entropy (corresponding to data compression) as a special case of relative entropy (corresponding to data differencing) with no initial data.
Is there an answer to this question: What can be classified as data differencing with corresponding data?

Answer:
unanswerable