Problem: Light-emitting diode:

This method involves coating LEDs of one color (mostly blue LEDs made of InGaN) with phosphors of different colors to form white light; the resultant LEDs are called phosphor-based or phosphor-converted white LEDs (pcLEDs). A fraction of the blue light undergoes the Stokes shift being transformed from shorter wavelengths to longer. Depending on the color of the original LED, phosphors of different colors can be employed. If several phosphor layers of distinct colors are applied, the emitted spectrum is broadened, effectively raising the color rendering index (CRI) value of a given LED.

What method involves coating LEDs of multiple color with phosphors of different colors?
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A: unanswerable

Problem: Most prime ministers in parliamentary systems are not appointed for a specific term in office and in effect may remain in power through a number of elections and parliaments. For example, Margaret Thatcher was only ever appointed prime minister on one occasion, in 1979. She remained continuously in power until 1990, though she used the assembly of each House of Commons after a general election to reshuffle her cabinet.
When did Thatcher last hold power?
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Answer: 1990

Q: What is a question about this article? If the question is unanswerable, say "unanswerable".
Popper puzzled over the stark contrast between the non-scientific character of Freud and Adler's theories in the field of psychology and the revolution set off by Einstein's theory of relativity in physics in the early 20th century. Popper thought that Einstein's theory, as a theory properly grounded in scientific thought and method, was highly "risky", in the sense that it was possible to deduce consequences from it which were, in the light of the then-dominant Newtonian physics, highly improbable (e.g., that light is deflected towards solid bodiesconfirmed by Eddington's experiments in 1919), and which would, if they turned out to be false, falsify the whole theory. In contrast, nothing could, even in principle, falsify psychoanalytic theories. He thus came to the conclusion that psychoanalytic theories had more in common with primitive myths than with genuine science.
Who though psychoanalytic theories had more in common with genuine science than myths?
A: unanswerable

Context and question: In some languages, including old Chinese, Thai, old Japanese, and Vietnamese, the same word can mean either blue or green. The Chinese character (pronounced qing in Mandarin, ao in Japanese, and thanh in Sino-Vietnamese) has a meaning that covers both blue and green; blue and green are traditionally considered shades of "". In more contemporary terms, they are (lan, in Mandarin) and (lu, in Mandarin) respectively. Japanese also has two terms that refer specifically to the color green, (midori, which is derived from the classical Japanese descriptive verb midoru "to be in leaf, to flourish" in reference to trees) and (guriin, which is derived from the English word "green"). However, in Japan, although the traffic lights have the same colors that other countries have, the green light is described using the same word as for blue, "aoi", because green is considered a shade of aoi; similarly, green variants of certain fruits and vegetables such as green apples, green shiso (as opposed to red apples and red shiso) will be described with the word "aoi". Vietnamese uses a single word for both blue and green, xanh, with variants such as xanh da troi (azure, lit. "sky blue"), lam (blue), and luc (green; also xanh la cay, lit. "leaf green").
What Chinese word for green is derived from English?
Answer: unanswerable

Question: The Montana Territory was formed on April 26, 1864, when the U.S. passed the Organic Act. Schools started forming in the area before it was officially a territory as families started settling into the area. The first schools were subscription schools that typically held in the teacher's home. The first formal school on record was at Fort Owen in Bitterroot valley in 1862. The students were Indian children and the children of Fort Owen employees. The first school term started in early winter and only lasted until February 28. Classes were taught by Mr. Robinson. Another early subscription school was started by Thomas Dimsdale in Virginia City in 1863. In this school students were charged $1.75 per week. The Montana Territorial Legislative Assembly had its inaugural meeting in 1864. The first legislature authorized counties to levy taxes for schools, which set the foundations for public schooling. Madison County was the first to take advantage of the newly authorized taxes and it formed fhe first public school in Virginia City in 1886. The first school year was scheduled to begin in January 1866, but severe weather postponed its opening until March. The first school year ran through the summer and didn't end until August 17. One of the first teachers at the school was Sarah Raymond. She was a 25-year-old woman who had traveled to Virginia City via wagon train in 1865. To become a certified teacher, Raymond took a test in her home and paid a $6 fee in gold dust to obtain a teaching certificate. With the help of an assistant teacher, Mrs. Farley, Raymond was responsible for teaching 50 to 60 students each day out of the 81 students enrolled at the school. Sarah Raymond was paid at a rate of $125 per month, and Mrs. Farley was paid $75 per month. There were no textbooks used in the school. In their place was an assortment of books brought in by various emigrants. Sarah quit teaching the following year, but would later become the Madison County superintendent of schools.
Is there an answer to this question: When was the first formal school on record?

Answer: 1862

Q: What is a question about this article? If the question is unanswerable, say "unanswerable".
In 1822, the American Colonization Society began sending African-American volunteers to the Pepper Coast to establish a colony for freed African Americans. By 1867, the ACS (and state-related chapters) had assisted in the migration of more than 13,000 African Americans to Liberia. These free African Americans and their descendants married within their community and came to identify as Americo-Liberians. Many were of mixed race and educated in American culture; they did not identify with the indigenous natives of the tribes they encountered. They intermarried largely within the colonial community, developing an ethnic group that had a cultural tradition infused with American notions of political republicanism and Protestant Christianity.
What did African Americans moved to Liberia keep from America?
A:
cultural tradition