Problem: Planck constant:

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 StefanBoltzmann law (187984). 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).

What about a hot object changes with the temperature?
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A: the colour of the light

Problem: Nigeria is a Federal Republic modelled after the United States, with executive power exercised by the president. It is influenced by the Westminster System model[citation needed] in the composition and management of the upper and lower houses of the bicameral legislature. The president presides as both Head of State and head of the national executive; the leader is elected by popular vote to a maximum of two 4-year terms. In the March 28, 2015 presidential election, General Muhammadu Buhari emerged victorious to become the Federal President of Nigeria, defeating then incumbent Goodluck Jonathan.
What houses does the Nigerian legislature have?
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Answer: upper and lower

Q: What is a question about this article? If the question is unanswerable, say "unanswerable".
The city's population in 2010 was 44% white (33.3% non-Hispanic white), 25.5% black (23% non-Hispanic black), 0.7% Native American, and 12.7% Asian. Hispanics of any race represented 28.6% of the population, while Asians constituted the fastest-growing segment of the city's population between 2000 and 2010; the non-Hispanic white population declined 3 percent, the smallest recorded decline in decades; and for the first time since the Civil War, the number of blacks declined over a decade.
What percentage of the city's population is African-American?
A: 25.5%

Context and question: Several subsets of Unicode are standardized: Microsoft Windows since Windows NT 4.0 supports WGL-4 with 652 characters, which is considered to support all contemporary European languages using the Latin, Greek, or Cyrillic script. Other standardized subsets of Unicode include the Multilingual European Subsets: MES-1 (Latin scripts only, 335 characters), MES-2 (Latin, Greek and Cyrillic 1062 characters) and MES-3A & MES-3B (two larger subsets, not shown here). Note that MES-2 includes every character in MES-1 and WGL-4.
How many Latin characters are supported in WGL-4?
Answer: unanswerable

Question: The verbs of most aspect pairs differ in one of two ways: by prefix or by suffix. In prefix pairs, the perfective verb has an added prefixfor example, the imperfective psat (to write, to be writing) compared with the perfective napsat (to write down, to finish writing). The most common prefixes are na-, o-, po-, s-, u-, vy-, z- and za-. In suffix pairs, a different infinitive ending is added to the perfective stem; for example, the perfective verbs koupit (to buy) and prodat (to sell) have the imperfective forms kupovat and prodavat. Imperfective verbs may undergo further morphology to make other imperfective verbs (iterative and frequentative forms), denoting repeated or regular action. The verb jit (to go) has the iterative form chodit (to go repeatedly) and the frequentative form chodivat (to go regularly).
Is there an answer to this question: What is added to the perfective stem in a prefix pair?

Answer: unanswerable

Question: The collation of all known variants of a text is referred to as a variorum, namely a work of textual criticism whereby all variations and emendations are set side by side so that a reader can track how textual decisions have been made in the preparation of a text for publication. The Bible and the works of William Shakespeare have often been the subjects of variorum editions, although the same techniques have been applied with less frequency to many other works, such as Walt Whitman's Leaves of Grass, and the prose writings of Edward Fitzgerald.
Is there an answer to this question: What is the name for the collation of all unknown variants of a text?

Answer:
unanswerable