Input: Read this: In 1902, the Siemens company developed a tantalum lamp filament. These lamps were more efficient than even graphitized carbon filaments and could operate at higher temperatures. Since tantalum metal has a lower resistivity than carbon, the tantalum lamp filament was quite long and required multiple internal supports. The metal filament had the property of gradually shortening in use; the filaments were installed with large loops that tightened in use. This made lamps in use for several hundred hours quite fragile. Metal filaments had the property of breaking and re-welding, though this would usually decrease resistance and shorten the life of the filament. General Electric bought the rights to use tantalum filaments and produced them in the US until 1913.
Question: Who bought the rights to use tantalum filaments and produce then in Canada in 1913?

Output: unanswerable


QUES: The opening years of the 1980s saw a number of changes in personnel and direction of established hard rock acts, including the deaths of Bon Scott, the lead singer of AC/DC, and John Bonham, drummer with Led Zeppelin. Whereas Zeppelin broke up almost immediately afterwards, AC/DC pressed on, recording the album Back in Black (1980) with their new lead singer, Brian Johnson. It became the fifth-highest-selling album of all time in the US and the second-highest-selling album in the world. Black Sabbath had split with original singer Ozzy Osbourne in 1979 and replaced him with Ronnie James Dio, formerly of Rainbow, giving the band a new sound and a period of creativity and popularity beginning with Heaven and Hell (1980). Osbourne embarked on a solo career with Blizzard of Ozz (1980), featuring American guitarist Randy Rhoads. Some bands, such as Queen, moved away from their hard rock roots and more towards pop rock, while others, including Rush with Moving Pictures (1981), began to return to a hard rock sound. The creation of thrash metal, which mixed heavy metal with elements of hardcore punk from about 1982, particularly by Metallica, Anthrax, Megadeth and Slayer, helped to create extreme metal and further remove the style from hard rock, although a number of these bands or their members would continue to record some songs closer to a hard rock sound. Kiss moved away from their hard rock roots toward pop metal: firstly removing their makeup in 1983 for their Lick It Up album, and then adopting the visual and sound of glam metal for their 1984 release, Animalize, both of which marked a return to commercial success. Pat Benatar was one of the first women to achieve commercial success in hard rock, with three successive Top 5 albums between 1980 and 1982.

What solo album did Randy Rhoads release in 1980?
What is the answer?
ANS: unanswerable


QUES: The southern group (South Estonian language) consists of the Tartu, Mulgi, Võru (Võro) and Setu (Seto) dialects. These are sometimes considered either variants of a South Estonian language, or separate languages altogether. Also, Seto and Võro distinguish themselves from each other less by language and more by their culture and their respective Christian confession.
 What dialects do not comprise the southern group?

ANS: unanswerable


During the turbulent reign of Wang Mang, Han lost control over the Tarim Basin, which was conquered by the Northern Xiongnu in AD 63 and used as a base to invade Han's Hexi Corridor in Gansu. Dou Gu (d. 88 AD) defeated the Northern Xiongnu at the Battle of Yiwulu in AD 73, evicting them from Turpan and chasing them as far as Lake Barkol before establishing a garrison at Hami. After the new Protector General of the Western Regions Chen Mu (d. AD 75) was killed by allies of the Xiongnu in Karasahr and Kucha, the garrison at Hami was withdrawn. At the Battle of Ikh Bayan in AD 89, Dou Xian (d. AD 92) defeated the Northern Xiongnu chanyu who then retreated into the Altai Mountains. After the Northern Xiongnu fled into the Ili River valley in AD 91, the nomadic Xianbei occupied the area from the borders of the Buyeo Kingdom in Manchuria to the Ili River of the Wusun people. The Xianbei reached their apogee under Tanshihuai (檀石槐) (d. AD 180), who consistently defeated Chinese armies. However, Tanshihuai's confederation disintegrated after his death.
If it is possible to answer this question, answer it for me (else, reply "unanswerable"): When did Chen Mu die?
Ah, so.. AD 75


Question: With an estimated population of 1,381,069 as of July 1, 2014, San Diego is the eighth-largest city in the United States and second-largest in California. It is part of the San Diego–Tijuana conurbation, the second-largest transborder agglomeration between the US and a bordering country after Detroit–Windsor, with a population of 4,922,723 people. San Diego is the birthplace of California and is known for its mild year-round climate, natural deep-water harbor, extensive beaches, long association with the United States Navy and recent emergence as a healthcare and biotechnology development center.
Try to answer this question if possible: Aside from healthcare, which employment sector has strongly emerged in San Diego?
Answer: biotechnology development


Input: Read this: Animals that characterize the Appalachian forests include five species of tree squirrels. The most commonly seen is the low to moderate elevation eastern gray squirrel (Sciurus carolinensis). Occupying similar habitat is the slightly larger fox squirrel (Sciurus niger) and the much smaller southern flying squirrel (Glaucomys volans). More characteristic of cooler northern and high elevation habitat is the red squirrel (Tamiasciurus hudsonicus), whereas the Appalachian northern flying squirrel (Glaucomys sabrinus fuscus), which closely resembles the southern flying squirrel, is confined to northern hardwood and spruce-fir forests.
Question: Which species is commonly found more in spruce-fir forests?

Output:
Appalachian northern flying squirrel