Problem: Planck constant:

A watt balance is an instrument for comparing two powers, one of which is measured in SI watts and the other of which is measured in conventional electrical units. From the definition of the conventional watt W90, this gives a measure of the product KJ2RK in SI units, where RK is the von Klitzing constant which appears in the quantum Hall effect. If the theoretical treatments of the Josephson effect and the quantum Hall effect are valid, and in particular assuming that RK = h/e2, the measurement of KJ2RK is a direct determination of the Planck constant.

What does a watt balance avoid?
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A: unanswerable


Problem: Philosophical empiricists hold no knowledge to be properly inferred or deduced unless it is derived from one's sense-based experience. This view is commonly contrasted with rationalism, which states that knowledge may be derived from reason independently of the senses. For example, John Locke held that some knowledge (e.g. knowledge of God's existence) could be arrived at through intuition and reasoning alone. Similarly Robert Boyle, a prominent advocate of the experimental method, held that we have innate ideas. The main continental rationalists (Descartes, Spinoza, and Leibniz) were also advocates of the empirical "scientific method".
Who were the main philosophical empiricists?
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Answer: unanswerable


Q: What is a question about this article? If the question is unanswerable, say "unanswerable".
The assumption that black-body radiation is thermal leads to an accurate prediction: the total amount of emitted energy goes up with the temperature according to a definite rule, the Stefan–Boltzmann law (1879–84). But it was also known that the colour of the light given off by a hot object changes with the temperature, so that "white hot" is hotter than "red hot". Nevertheless, Wilhelm Wien discovered the mathematical relationship between the peaks of the curves at different temperatures, by using the principle of adiabatic invariance. At each different temperature, the curve is moved over by Wien's displacement law (1893). Wien also proposed an approximation for the spectrum of the object, which was correct at high frequencies (short wavelength) but not at low frequencies (long wavelength). It still was not clear why the spectrum of a hot object had the form that it has (see diagram).
Who discovered the mathematical relationship between peaks and curves of light at different temperatures?
A: Wilhelm Wien


Context and question: Some countries are eliminating or reducing climate disrupting subsidies and Belgium, France, and Japan have phased out all subsidies for coal. Germany is reducing its coal subsidy. The subsidy dropped from $5.4 billion in 1989 to $2.8 billion in 2002, and in the process Germany lowered its coal use by 46 percent. China cut its coal subsidy from $750 million in 1993 to $240 million in 1995 and more recently has imposed a high-sulfur coal tax. However, the United States has been increasing its support for the fossil fuel and nuclear industries.
 No countries have phased out all subsidies for what substance?
Answer: unanswerable


Question: iPods have been criticized for alleged short life-span and fragile hard drives. A 2005 survey conducted on the MacInTouch website found that the iPod line had an average failure rate of 13.7% (although they note that comments from respondents indicate that "the true iPod failure rate may be lower than it appears"). It concluded that some models were more durable than others. In particular, failure rates for iPods employing hard drives was usually above 20% while those with flash memory had a failure rate below 10%. In late 2005, many users complained that the surface of the first generation iPod Nano can become scratched easily, rendering the screen unusable. A class action lawsuit was also filed. Apple initially considered the issue a minor defect, but later began shipping these iPods with protective sleeves.[citation needed]
Is there an answer to this question: Which type of iPod storage proved more reliable than hard drive storage?

Answer: flash memory


Q: What is a question about this article? If the question is unanswerable, say "unanswerable".
The competition is open to any club down to Level 10 of the English football league system which meets the eligibility criteria. All clubs in the top four levels (the Premier League and the three divisions of the Football League) are automatically eligible. Clubs in the next six levels (non-league football) are also eligible provided they have played in either the FA Cup, FA Trophy or FA Vase competitions in the previous season. Newly formed clubs, such as F.C. United of Manchester in 2005–06 and also 2006–07, may not therefore play in the FA Cup in their first season. All clubs entering the competition must also have a suitable stadium.
What season can newly formed clubs start playing in?
A:
unanswerable