Input: Read this: In the last two decades, photovoltaics (PV), also known as solar PV, has evolved from a pure niche market of small scale applications towards becoming a mainstream electricity source. A solar cell is a device that converts light directly into electricity using the photoelectric effect. The first solar cell was constructed by Charles Fritts in the 1880s. In 1931 a German engineer, Dr Bruno Lange, developed a photo cell using silver selenide in place of copper oxide. Although the prototype selenium cells converted less than 1% of incident light into electricity, both Ernst Werner von Siemens and James Clerk Maxwell recognized the importance of this discovery. Following the work of Russell Ohl in the 1940s, researchers Gerald Pearson, Calvin Fuller and Daryl Chapin created the crystalline silicon solar cell in 1954. These early solar cells cost 286 USD/watt and reached efficiencies of 4.5–6%. By 2012 available efficiencies exceed 20% and the maximum efficiency of research photovoltaics is over 40%.
Question: In the 1880s, who constructed the first solar cell?

Output: Charles Fritts


QUES: Multiracial Americans are Americans who have mixed ancestry of "two or more races". The term may also include Americans of mixed-race ancestry who self-identify with just one group culturally and socially (cf. the one-drop rule). In the 2010 US census, approximately 9 million individuals, or 2.9% of the population, self-identified as multiracial. There is evidence that an accounting by genetic ancestry would produce a higher number, but people live according to social and cultural identities, not DNA. Historical reasons, including slavery creating a racial caste and the European-American suppression of Native Americans, often led people to identify or be classified by only one ethnicity, generally that of the culture in which they were raised. Prior to the mid-20th century, many people hid their multiracial heritage because of racial discrimination against minorities. While many Americans may be biologically multiracial, they often do not know it or do not identify so culturally, any more than they maintain all the differing traditions of a variety of national ancestries.

How many individuals identified as multiracial in the 2000 US census?
What is the answer?
ANS: unanswerable


QUES: Traditionally, Espanyol was seen by the vast majority of Barcelona's citizens as a club which cultivated a kind of compliance to the central authority, in stark contrast to Barça's revolutionary spirit. Also in the 1960s and 1970s, while FC Barcelona acted as an integrating force for Catalonia's new arrivals from poorer regions of Spain expecting to find a better life, Espanyol drew their support mainly from sectors close to the regime such as policemen, military officers, civil servants and career fascists.
How was Espanyol viewed as being toward Spanish authority by the people of Barcelona?

ANS: compliance


Czech contains ten basic vowel phonemes, and three more found only in loanwords. They are /a/, /ɛ/, /ɪ/, /o/, and /u/, their long counterparts /aː/, /ɛː/, /iː/, /oː/ and /uː/, and three diphthongs, /ou̯/, /au̯/ and /ɛu̯/. The latter two diphthongs and the long /oː/ are exclusive to loanwords. Vowels are never reduced to schwa sounds when unstressed. Each word usually has primary stress on its first syllable, except for enclitics (minor, monosyllabic, unstressed syllables). In all words of more than two syllables, every odd-numbered syllable receives secondary stress. Stress is unrelated to vowel length, and the possibility of stressed short vowels and unstressed long vowels can be confusing to students whose native language combines the features (such as English).
If it is possible to answer this question, answer it for me (else, reply "unanswerable"): What a few exceptions where is the primary word stress in Czech?
Ah, so.. first syllable


Question: Television money had also become much more important; the Football League received £6.3 million for a two-year agreement in 1986, but when that deal was renewed in 1988, the price rose to £44 million over four years. The 1988 negotiations were the first signs of a breakaway league; ten clubs threatened to leave and form a "super league", but were eventually persuaded to stay. As stadiums improved and match attendance and revenues rose, the country's top teams again considered leaving the Football League in order to capitalise on the growing influx of money being pumped into the sport.
Try to answer this question if possible: When was the first year that clubs threatened to leave the Football League?
Answer: 1988


Input: Read this: Due to the expansion of trade and its geographical proximity, Kiev became the most important trade centre and chief among the communes; therefore the leader of Kiev gained political "control" over the surrounding areas. This princedom emerged from a coalition of traditional patriarchic family communes banded together in an effort to increase the applicable workforce and expand the productivity of the land. This union developed the first major cities in the Rus' and was the first notable form of self-government. As these communes became larger, the emphasis was taken off the family holdings and placed on the territory that surrounded. This shift in ideology became known as the verv'.
Question: What caused the decline of Kiev political power?

Output:
unanswerable