Problem: Czech language:

Czech, the official language of the Czech Republic (a member of the European Union since 2004), is one of the EU's official languages and the 2012 Eurobarometer survey found that Czech was the foreign language most often used in Slovakia. Economist Jonathan van Parys collected data on language knowledge in Europe for the 2012 European Day of Languages. The five countries with the greatest use of Czech were the Czech Republic (98.77 percent), Slovakia (24.86 percent), Portugal (1.93 percent), Poland (0.98 percent) and Germany (0.47 percent).

What percentage of people in Portugal speak German?
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A: unanswerable

Problem: A HDI below 0.5 is considered to represent "low development". All 22 countries in that category are located in Africa. The highest-scoring Sub-Saharan countries, Gabon and South Africa, are ranked 119th and 121st, respectively. Nine countries departed from this category this year and joined the "medium development" group.
On which continent are all 23 of the low development countries located?
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Answer: unanswerable

Q: What is a question about this article? If the question is unanswerable, say "unanswerable".
There are several types of multi-color white LEDs: di-, tri-, and tetrachromatic white LEDs. Several key factors that play among these different methods, include color stability, color rendering capability, and luminous efficacy. Often, higher efficiency will mean lower color rendering, presenting a trade-off between the luminous efficacy and color rendering. For example, the dichromatic white LEDs have the best luminous efficacy (120 lm/W), but the lowest color rendering capability. However, although tetrachromatic white LEDs have excellent color rendering capability, they often have poor luminous efficacy. Trichromatic white LEDs are in between, having both good luminous efficacy (>70 lm/W) and fair color rendering capability.
What luminous efficacy does non-trichromatic white LEDs have?
A: unanswerable

Context and question: The light from LEDs can be modulated very quickly so they are used extensively in optical fiber and free space optics communications. This includes remote controls, such as for TVs, VCRs, and LED Computers, where infrared LEDs are often used. Opto-isolators use an LED combined with a photodiode or phototransistor to provide a signal path with electrical isolation between two circuits. This is especially useful in medical equipment where the signals from a low-voltage sensor circuit (usually battery-powered) in contact with a living organism must be electrically isolated from any possible electrical failure in a recording or monitoring device operating at potentially dangerous voltages. An optoisolator also allows information to be transferred between circuits not sharing a common ground potential.
Where are opto-isolators found?
Answer: medical equipment

Question: Some modern day physicists and science writerssuch as Paul Davies and John Gribbinhave argued that materialism has been disproven by certain scientific findings in physics, such as quantum mechanics and chaos theory. In 1991, Gribbin and Davies released their book The Matter Myth, the first chapter of which, "The Death of Materialism", contained the following passage:
Is there an answer to this question: When was John Gribbin born?

Answer: unanswerable

QUES: The growth of the Internet, and particularly distributed search engines like Kazaa and Gnutella, have represented a challenge for copyright policy. The Recording Industry Association of America, in particular, has been on the front lines of the fight against copyright infringement, which the industry calls "piracy". The industry has had victories against some services, including a highly publicized case against the file-sharing company Napster, and some people have been prosecuted for sharing files in violation of copyright. The electronic age has seen an increase in the attempt to use software-based digital rights management tools to restrict the copying and use of digitally based works. Laws such as the Digital Millennium Copyright Act have been enacted, that use criminal law to prevent any circumvention of software used to enforce digital rights management systems. Equivalent provisions, to prevent circumvention of copyright protection have existed in EU for some time, and are being expanded in, for example, Article 6 and 7 the Copyright Directive. Other examples are Article 7 of the Software Directive of 1991 (91/250/EEC), and the Conditional Access Directive of 1998 (98/84/EEC). This can hinder legal uses, affecting public domain works, limitations and exceptions to copyright, or uses allowed by the copyright holder. Some copyleft licenses, like GNU GPL 3, are designed to counter that. Laws may permit circumvention under specific conditions like when it is necessary to achieve interoperability with the circumventor's program, or for accessibility reasons; however, distribution of circumvention tools or instructions may be illegal.

What does the recording industry call piracy?
What is the answer?
ANS:
copyright infringement