Input: Read this: The first high-brightness blue LED was demonstrated by Shuji Nakamura of Nichia Corporation in 1994 and was based on InGaN. In parallel, Isamu Akasaki and Hiroshi Amano in Nagoya were working on developing the important GaN nucleation on sapphire substrates and the demonstration of p-type doping of GaN. Nakamura, Akasaki and Amano were awarded the 2014 Nobel prize in physics for their work. In 1995, Alberto Barbieri at the Cardiff University Laboratory (GB) investigated the efficiency and reliability of high-brightness LEDs and demonstrated a "transparent contact" LED using indium tin oxide (ITO) on (AlGaInP/GaAs).
Question: What substance did Barbieri use in his work with low-brightness LED?

Output: unanswerable

QUES: By total area (water as well as land), the United States is either slightly larger or smaller than the People's Republic of China, making it the world's third or fourth largest country. China and the United States are smaller than Russia and Canada in total area, but are larger than Brazil. By land area only (exclusive of waters), the United States is the world's third largest country, after Russia and China, with Canada in fourth. Whether the US or China is the third largest country by total area depends on two factors: (1) The validity of China's claim on Aksai Chin and Trans-Karakoram Tract. Both these territories are also claimed by India, so are not counted; and (2) How US calculates its own surface area. Since the initial publishing of the World Factbook, the CIA has updated the total area of United States a number of times.

Brazil is larger than what other two countries?
What is the answer?
ANS: unanswerable

QUES: The evolution of Proto-Greek should be considered within the context of an early Paleo-Balkan sprachbund that makes it difficult to delineate exact boundaries between individual languages. The characteristically Greek representation of word-initial laryngeals by prothetic vowels is shared, for one, by the Armenian language, which also seems to share some other phonological and morphological peculiarities of Greek; this has led some linguists to propose a hypothetical closer relationship between Greek and Armenian, although evidence remains scant.
How much evidence of the link between the languages is currently available ?

ANS: linguists to propose a hypothetical closer relationship between Greek and Armenian, although evidence remains scant.

The dollar was first based on the value and look of the Spanish dollar, used widely in Spanish America from the 16th to the 19th centuries. The first dollar coins issued by the United States Mint (founded 1792) were similar in size and composition to the Spanish dollar, minted in Mexico and Peru. The Spanish, U.S. silver dollars, and later, Mexican silver pesos circulated side by side in the United States, and the Spanish dollar and Mexican peso remained legal tender until the Coinage Act of 1857. The coinage of various English colonies also circulated. The lion dollar was popular in the Dutch New Netherland Colony (New York), but the lion dollar also circulated throughout the English colonies during the 17th century and early 18th century. Examples circulating in the colonies were usually worn so that the design was not fully distinguishable, thus they were sometimes referred to as "dog dollars".
If it is possible to answer this question, answer it for me (else, reply "unanswerable"): When was the Spanish Mint founded?
Ah, so.. unanswerable

Question: David Attenborough was later granted sabbatical leave from his job as Controller to work with the BBC Natural History Unit which had existed since the 1950s. This unit is now famed throughout the world for producing high quality programmes with Attenborough such as Life on Earth, The Private Life of Plants, The Blue Planet, The Life of Mammals, Planet Earth and Frozen Planet.
Try to answer this question if possible: Who joined the BBC History Unit?
Answer: unanswerable

QUES: Ann Arbor's residential neighborhoods contain architectural styles ranging from classic 19th-century and early-20th-century designs to ranch-style houses. Among these homes are a number of kit houses built in the early 20th century. Contemporary-style houses are farther from the downtown district. Surrounding the University of Michigan campus are houses and apartment complexes occupied primarily by student renters. Tower Plaza, a 26-story condominium building located between the University of Michigan campus and downtown, is the tallest building in Ann Arbor. The 19th-century buildings and streetscape of the Old West Side neighborhood have been preserved virtually intact; in 1972, the district was listed on the National Register of Historic Places, and it is further protected by city ordinances and a nonprofit preservation group.
Which is the tallest building in Ann Arbor?

ANS:
Tower Plaza