Problem: Data compression:

Data compression can be viewed as a special case of data differencing: Data differencing consists of producing a difference given a source and a target, with patching producing a target given a source and a difference, while data compression consists of producing a compressed file given a target, and decompression consists of producing a target given only a compressed file. Thus, one can consider data compression as data differencing with empty source data, the compressed file corresponding to a "difference from nothing." This is the same as considering absolute entropy (corresponding to data compression) as a special case of relative entropy (corresponding to data differencing) with no initial data.

What means producing a target given only a special case?
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A: unanswerable


Problem: A number of special controllers designed for use with specific games were released for the system, though very few such devices proved particularly popular. Such devices included, but were not limited to, the Zapper (a light gun), the R.O.B., and the Power Pad. The original Famicom featured a deepened DA-15 expansion port on the front of the unit, which was used to connect most auxiliary devices. On the NES, these special controllers were generally connected to one of the two control ports on the front of the console.
How were the special controllers connected to the NES?
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Answer: control ports on the front


Q: What is a question about this article? If the question is unanswerable, say "unanswerable".
Four boarders at his parents' apartments became Chopin's intimates: Tytus Woyciechowski, Jan Nepomucen Białobłocki, Jan Matuszyński and Julian Fontana; the latter two would become part of his Paris milieu. He was friendly with members of Warsaw's young artistic and intellectual world, including Fontana, Józef Bohdan Zaleski and Stefan Witwicki. He was also attracted to the singing student Konstancja Gładkowska. In letters to Woyciechowski, he indicated which of his works, and even which of their passages, were influenced by his fascination with her; his letter of 15 May 1830 revealed that the slow movement (Larghetto) of his Piano Concerto No. 1 (in E minor) was secretly dedicated to her – "It should be like dreaming in beautiful springtime – by moonlight." His final Conservatory report (July 1829) read: "Chopin F., third-year student, exceptional talent, musical genius."
What four boys from his family's boarding house became friends with Chopin?
A: Tytus Woyciechowski, Jan Nepomucen Białobłocki, Jan Matuszyński and Julian Fontana


Context and question: Early history of Shaivism is difficult to determine. However, the Śvetāśvatara Upanishad (400 – 200 BCE) is considered to be the earliest textual exposition of a systematic philosophy of Shaivism. Shaivism is represented by various philosophical schools, including non-dualist (abheda), dualist (bheda), and non-dualist-with-dualist (bhedābheda) perspectives. Vidyaranya in his works mentions three major schools of Shaiva thought— Pashupata Shaivism, Shaiva Siddhanta and Pratyabhijña (Kashmir Shaivism).
When was the text on Shaivism written?
Answer: 400 – 200 BCE


Question: In the colonial years, while conditions were more fluid, white women, indentured servant or free, and African men, servant, slave or free, made unions. Because the women were free, their mixed-race children were born free; they and their descendants formed most of the families of free people of color during the colonial period in Virginia. The scholar Paul Heinegg found that eighty percent of the free people of color in North Carolina in censuses from 1790–1810 could be traced to families free in Virginia in colonial years.
Is there an answer to this question: What percentage of free people of color in Virginia can be traced to families in North Carolina?

Answer: unanswerable


QUES: Inner and outer vestibules lead to the octagonal chapter house, which is of exceptional architectural purity. It is built in a Geometrical Gothic style with an octagonal crypt below. A pier of eight shafts carries the vaulted ceiling. To the sides are blind arcading, remains of 14th-century paintings and numerous stone benches above which are innovatory large 4-light quatre-foiled windows. These are virtually contemporary with the Sainte-Chapelle, Paris.

The architecture of the chapel house is contemporary with what?
What is the answer?
ANS:
unanswerable