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 shift does blue light undergo in the pcLEDs method?
---
A: Stokes

Problem: Hunting and gathering was humanity's first and most successful adaptation, occupying at least 90 percent of human history. Following the invention of agriculture, hunter-gatherers have been displaced or conquered by farming or pastoralist groups in most parts of the world.
What was the first way humans used to find food?
---
Answer: Hunting and gathering

Q: What is a question about this article? If the question is unanswerable, say "unanswerable".
In certain historical Christian, Islamic and Jewish cultures, among others, espousing ideas deemed heretical has been and in some cases still is subjected not merely to punishments such as excommunication, but even to the death penalty.
What religions believe new ideas is punishable?
A: unanswerable

Context and question: Today the boundaries of the Ukrainian language to the Russian language are still not drawn clearly, with an intermediate dialect between them, called Surzhyk, developing in Ukraine.
Surzhyk is a dialect intermediate between the Ukrainian language and what other language?
Answer: Russian

Question: The fossil record suggests that the last few million years featured the greatest biodiversity in history. However, not all scientists support this view, since there is uncertainty as to how strongly the fossil record is biased by the greater availability and preservation of recent geologic sections. Some scientists believe that corrected for sampling artifacts, modern biodiversity may not be much different from biodiversity 300 million years ago., whereas others consider the fossil record reasonably reflective of the diversification of life. Estimates of the present global macroscopic species diversity vary from 2 million to 100 million, with a best estimate of somewhere near 9 million, the vast majority arthropods. Diversity appears to increase continually in the absence of natural selection.
Is there an answer to this question: What appears increase continually in the absence of natural selection?

Answer: Diversity

In the Roman era, copper was principally mined on Cyprus, the origin of the name of the metal from aes yprium (metal of Cyprus), later corrupted to uprum, from which the words copper (English), cuivre (French), Koper (Dutch) and Kupfer (German) are all derived. Its compounds are commonly encountered as copper(II) salts, which often impart blue or green colors to minerals such as azurite, malachite and turquoise and have been widely used historically as pigments. Architectural structures built with copper corrode to give green verdigris (or patina). Decorative art prominently features copper, both by itself and in the form of pigments.
If it is possible to answer this question, answer it for me (else, reply "unanswerable"): What componds are common in copper?
Ah, so..
copper(II) salts