Q: What is a question about this article? If the question is unanswerable, say "unanswerable".
The fighter aircraft of the USAF are small, fast, and maneuverable military aircraft primarily used for air-to-air combat. Many of these fighters have secondary ground-attack capabilities, and some are dual-roled as fighter-bombers (e.g., the F-16 Fighting Falcon); the term "fighter" is also sometimes used colloquially for dedicated ground-attack aircraft. Other missions include interception of bombers and other fighters, reconnaissance, and patrol. The F-16 is currently used by the USAF Air Demonstration squadron, the Thunderbirds, while a small number of both man-rated and non-man-rated F-4 Phantom II are retained as QF-4 aircraft for use as Full Scale Aerial Targets (FSAT) or as part of the USAF Heritage Flight program. These extant QF-4 aircraft are being replaced in the FSAT role by early model F-16 aircraft converted to QF-16 configuration. The USAF has 2,025 fighters in service as of September 2012.
What are the QF-4 aircraft being replaced by the US Air Force?
A: early model F-16 aircraft converted to QF-16 configuration

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Rejecting offers to direct Jaws 2, King Kong and Superman, Spielberg and actor Richard Dreyfuss re-convened to work on a film about UFOs, which became Close Encounters of the Third Kind (1977). One of the rare films both written and directed by Spielberg, Close Encounters was a critical and box office hit, giving Spielberg his first Best Director nomination from the Academy as well as earning six other Academy Awards nominations. It won Oscars in two categories (Cinematography, Vilmos Zsigmond, and a Special Achievement Award for Sound Effects Editing, Frank E. Warner). This second blockbuster helped to secure Spielberg's rise. His next film, 1941, a big-budgeted World War II farce, was not nearly as successful and though it grossed over $92.4 million worldwide (and did make a small profit for co-producing studios Columbia and Universal) it was seen as a disappointment, mainly with the critics.
How much did '1941' earn?
A: over $92.4 million worldwide

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People are usually well informed about their health status, the positive and negative effects of their behaviour on their health and their use of health care services. Yet their perceptions of their health can differ from what administrative and examination-based data show about levels of illness within populations. Thus, survey results based on self-reporting at the household level complement other data on health status and the use of services. Only one third of adults rated their health as good or very good in Portugal (Kasmel et al., 2004). This is the lowest of the Eur-A countries reporting and reflects the relatively adverse situation of the country in terms of mortality and selected morbidity.
What survey results complement on data on health status?
A: self-reporting at the household level

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Slack (2003) compares three groups that conducted biological research at Yale during overlapping periods between 1910 and 1970. Yale proved important as a site for this research. The leaders of these groups were Ross Granville Harrison, Grace E. Pickford, and G. Evelyn Hutchinson, and their members included both graduate students and more experienced scientists. All produced innovative research, including the opening of new subfields in embryology, endocrinology, and ecology, respectively, over a long period of time. Harrison's group is shown to have been a classic research school; Pickford's and Hutchinson's were not. Pickford's group was successful in spite of her lack of departmental or institutional position or power. Hutchinson and his graduate and postgraduate students were extremely productive, but in diverse areas of ecology rather than one focused area of research or the use of one set of research tools. Hutchinson's example shows that new models for research groups are needed, especially for those that include extensive field research.
What didn't Hutchinson's group research?
A:
unanswerable