Problem: Solar energy:

The International Organization for Standardization has established a number of standards relating to solar energy equipment. For example, ISO 9050 relates to glass in building while ISO 10217 relates to the materials used in solar water heaters.

What is the name of the standard related to the materials used in solar water heaters?
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A: ISO 10217

Problem: The primary source of rain in the Sahara is the equatorial low a continuous belt of low-pressure systems near the equator which bring the brief, short and irregular rainy season to the Sahel and the southern Sahara. The Sahara doesn't lack precipitation because of a lack of moisture, but due to the lack of a precipitation-generating mechanism. Rainfall in this giant desert has to overcome the physical and atmospheric barriers that normally prevent the production of precipitation. The harsh climate of the Sahara is characterized by extremely low, unreliable, highly erratic rainfall; extremely high sunshine duration values; high temperatures year-round; negligible rates of relative humidity, a significant diurnal temperature variation and extremely high levels of potential evaporation which are the highest recorded worldwide.
What aids the production of percipitation in the Sahara?
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Answer: unanswerable

Q: What is a question about this article? If the question is unanswerable, say "unanswerable".
These different explorations of 'identity' demonstrate how difficult a concept it is to pin down. Since identity is a virtual thing, it is impossible to define it empirically. Discussions of identity use the term with different meanings, from fundamental and abiding sameness, to fluidity, contingency, negotiated and so on. Brubaker and Cooper note a tendency in many scholars to confuse identity as a category of practice and as a category of analysis (Brubaker & Cooper 2000, p. 5). Indeed, many scholars demonstrate a tendency to follow their own preconceptions of identity, following more or less the frameworks listed above, rather than taking into account the mechanisms by which the concept is crystallised as reality. In this environment, some analysts, such as Brubaker and Cooper, have suggested doing away with the concept completely (Brubaker & Cooper 2000, p. 1). Others, by contrast, have sought to introduce alternative concepts in an attempt to capture the dynamic and fluid qualities of human social self-expression. Hall (1992, 1996), for example, suggests treating identity as a process, to take into account the reality of diverse and ever-changing social experience. Some scholars have introduced the idea of identification, whereby identity is perceived as made up of different components that are 'identified' and interpreted by individuals. The construction of an individual sense of self is achieved by personal choices regarding who and what to associate with. Such approaches are liberating in their recognition of the role of the individual in social interaction and the construction of identity.
What is it impossible to do with identity?
A: define it empirically

Context and question: Tech media website CNET gave new Super Slim 4 out of 5 stars ("Excellent"), saying "The Super Slim PlayStation 3 shrinks a powerful gaming machine into an even tinier package while maintaining the same features as its predecessors: a great gaming library and a strong array of streaming services [...]", whilst also criticising the "cheap" design and disc-loader, stating: "Sometimes [the cover] doesn't catch and you feel like you're using one of those old credit card imprinter machines. In short, it feels cheap. You don't realize how convenient autoloading disc trays are until they're gone. Whether it was to cut costs or save space, this move is ultimately a step back." The criticism also was due to price, stating the cheapest Super Slim model was still more expensive than the cheapest Slim model, and that the smaller size and bigger hard drive shouldn't be considered an upgrade when the hard drive on a Slim model is easily removed and replaced. They did praise that the hard drive of the Super Slim model is "the easiest yet. Simply sliding off the side panel reveals the drive bay, which can quickly be unscrewed." They also stated that whilst the Super Slim model is not in any way an upgrade, it could be an indicator as to what's to come. "It may not be revolutionary, but the Super Slim PS3 is the same impressive machine in a much smaller package. There doesn't seem to be any reason for existing PS3 owners to upgrade, but for the prospective PS3 buyer, the Super Slim is probably the way to go if you can deal with not having a slot-loading disc drive."
What component of the Super Slim did CNET call "the easiest yet"?
Answer: hard drive

Question: In the 1990s, Dell switched from using primarily ATX motherboards and PSU to using boards and power supplies with mechanically identical but differently wired connectors. This meant customers wishing to upgrade their hardware would have to replace parts with scarce Dell-compatible parts instead of commonly available parts. While motherboard power connections reverted to the industry standard in 2003, Dell continues to remain secretive about their motherboard pin-outs for peripherals (such as MMC readers and power on/off switches and LEDs).
Is there an answer to this question: With what kind of parts were consumers unable to upgrade their Dell systems with?

Answer: unanswerable

Q: What is a question about this article? If the question is unanswerable, say "unanswerable".
A government report covered by the Guardian in 2002 indicates that between 1940 and 1979, the Ministry of Defence "turned large parts of the country into a giant laboratory to conduct a series of secret germ warfare tests on the public" and many of these tests "involved releasing potentially dangerous chemicals and micro-organisms over vast swaths of the population without the public being told." The Ministry of Defence claims that these trials were to simulate germ warfare and that the tests were harmless. Still, families who have been in the area of many of the tests are experiencing children with birth defects and physical and mental handicaps and many are asking for a public inquiry. According to the report these tests affected estimated millions of people including one period between 1961 and 1968 where "more than a million people along the south coast of England, from Torquay to the New Forest, were exposed to bacteria including e.coli and bacillus globigii, which mimics anthrax." Two scientists commissioned by the Ministry of Defence stated that these trials posed no risk to the public. This was confirmed by Sue Ellison, a representative of Porton Down who said that the results from these trials "will save lives, should the country or our forces face an attack by chemical and biological weapons." Asked whether such tests are still being carried out, she said: "It is not our policy to discuss ongoing research." It is unknown whether or not the harmlessness of the trials was known at the time of their occurrence.
What was the purpose of Porton Down releasing germs on the public unknowingly?
A:
unanswerable