Problem: Anti-aircraft warfare:

Anti-aircraft warfare or counter-air defence is defined by NATO as "all measures designed to nullify or reduce the effectiveness of hostile air action." They include ground-and air-based weapon systems, associated sensor systems, command and control arrangements and passive measures (e.g. barrage balloons). It may be used to protect naval, ground, and air forces in any location. However, for most countries the main effort has tended to be 'homeland defence'. NATO refers to airborne air defence as counter-air and naval air defence as anti-aircraft warfare. Missile defence is an extension of air defence as are initiatives to adapt air defence to the task of intercepting any projectile in flight.

What is the primary effort been for most countries when it comes to anti-aircraft warfare?
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A: homeland defence

Problem: The earliest recorded account of a circadian process dates from the 4th century B.C.E., when Androsthenes, a ship captain serving under Alexander the Great, described diurnal leaf movements of the tamarind tree. The observation of a circadian or diurnal process in humans is mentioned in Chinese medical texts dated to around the 13th century, including the Noon and Midnight Manual and the Mnemonic Rhyme to Aid in the Selection of Acu-points According to the Diurnal Cycle, the Day of the Month and the Season of the Year.
What philosophers first described the diurnal process in humans?
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Answer: unanswerable

Q: What is a question about this article? If the question is unanswerable, say "unanswerable".
Since these problems surfaced, Microsoft has attempted to modify the console to improve its reliability. Modifications include a reduction in the number, size, and placement of components, the addition of dabs of epoxy on the corners and edges of the CPU and GPU as glue to prevent movement relative to the board during heat expansion, and a second GPU heatsink to dissipate more heat. With the release of the redesigned Xbox 360 S, the warranty for the newer models does not include the three-year extended coverage for "General Hardware Failures". The newer Xbox 360 S model indicates system overheating when the console's power button begins to flash red, unlike previous models where the first and third quadrant of the ring would light up red around the power button if overheating occurred. The system will then warn the user of imminent system shutdown until the system has cooled, whereas a flashing power button that alternates between green and red is an indication of a "General Hardware Failure" unlike older models where three of the quadrants would light up red.
The third and first quadrant turn what two colors?
A: unanswerable

Context and question: GE has a history of some of its activities giving rise to large-scale air and water pollution. Based on year 2000 data, researchers at the Political Economy Research Institute listed the corporation as the fourth-largest corporate producer of air pollution in the United States, with more than 4.4 million pounds per year (2,000 tons) of toxic chemicals released into the air. GE has also been implicated in the creation of toxic waste. According to EPA documents, only the United States Government, Honeywell, and Chevron Corporation are responsible for producing more Superfund toxic waste sites.
Which organization identified GE as the fourth largest corporate producer of air pollution in the US?
Answer: Political Economy Research Institute

Question: The francophone Swiss Rodolphe Topffer produced comic strips beginning in 1827, and published theories behind the form. Cartoons appeared widely in newspapers and magazines from the 19th century. The success of Zig et Puce in 1925 popularized the use of speech balloons in European comics, after which Franco-Belgian comics began to dominate. The Adventures of Tintin, with its signature clear line style, was first serialized in newspaper comics supplements beginning in 1929, and became an icon of Franco-Belgian comics.
Is there an answer to this question: What century had comics in local production?

Answer: unanswerable

Backup and Restore, the backup component of Windows, is deprecated. It still ships with Windows 8 and continues to work on preset schedules, but is pushed to the background and can only be accessed through a Control Panel applet called "Windows 7 File Recovery".:76 Shadow Copy, a component of Windows Explorer that once saved previous versions of changed files, no longer protects local files and folders. It can only access previous versions of shared files stored on a Windows Server computer.:74 The subsystem on which these components worked, however, is still available for other software to use.:74
If it is possible to answer this question, answer it for me (else, reply "unanswerable"): What is :74 used for?
Ah, so..
other software