Problem: United States dollar:

The symbol $, usually written before the numerical amount, is used for the U.S. dollar (as well as for many other currencies). The sign was the result of a late 18th-century evolution of the scribal abbreviation "ps" for the peso, the common name for the Spanish dollars that were in wide circulation in the New World from the 16th to the 19th centuries. These Spanish pesos or dollars were minted in Spanish America, namely in Mexico City, Potosí, Bolivia; and Lima, Peru. The p and the s eventually came to be written over each other giving rise to $.

Which century signalled the end of the Spanish dollar?
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A: 19th


Problem: The synthesis of urea by Friedrich Wöhler opened a new research field, organic chemistry, and by the end of the 19th century, scientists were able to synthesize hundreds of organic compounds. The later part of the 19th century saw the exploitation of the Earth's petrochemicals, after the exhaustion of the oil supply from whaling. By the 20th century, systematic production of refined materials provided a ready supply of products which provided not only energy, but also synthetic materials for clothing, medicine, and everyday disposable resources. Application of the techniques of organic chemistry to living organisms resulted in physiological chemistry, the precursor to biochemistry. The 20th century also saw the integration of physics and chemistry, with chemical properties explained as the result of the electronic structure of the atom. Linus Pauling's book on The Nature of the Chemical Bond used the principles of quantum mechanics to deduce bond angles in ever-more complicated molecules. Pauling's work culminated in the physical modelling of DNA, the secret of life (in the words of Francis Crick, 1953). In the same year, the Miller–Urey experiment demonstrated in a simulation of primordial processes, that basic constituents of proteins, simple amino acids, could themselves be built up from simpler molecules.
What scientific field did Wohler discover?
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Answer: organic chemistry


Q: What is a question about this article? If the question is unanswerable, say "unanswerable".
Shōen holders had access to manpower and, as they obtained improved military technology (such as new training methods, more powerful bows, armor, horses, and superior swords) and faced worsening local conditions in the ninth century, military service became part of shōen life. Not only the shōen but also civil and religious institutions formed private guard units to protect themselves. Gradually, the provincial upper class was transformed into a new military elite based on the ideals of the bushi (warrior) or samurai (literally, one who serves).
What deprived the Shoen of manpower?
A: unanswerable


Context and question: His organisational skills led him to a career in the Roman Curia, the papal civil service. In 1931, Pacelli appointed him to teach history at the Papal Academy for Diplomats In 1937, after his mentor Giuseppe Pizzardo was named a cardinal and was succeeded by Domenico Tardini, Montini was named Substitute for Ordinary Affairs under Cardinal Pacelli, the Secretary of State under Pope Pius XI. From Pius XI, whom he viewed with awe, he adopted the view, that learning is a life long process, and that history was the magister vitae teacher of life His immediate supervisor in the Vatican was Domenico Tardini, with whom he got along well. The election of Pacelli to the papacy in 1939, anticipated by everybody and openly promoted by Pope Pius XI in his last years, was a good omen for Montini, whose position was confirmed in the position under the new Cardinal Secretary of State Luigi Maglione. He met the pope every morning until 1954 and thus developed a rather close relationship:
What type of natural ability helped Montini in his career in the Roman Curia?
Answer: organisational skills


Question: The main industries are mineral based, agriculture based, and textile based. Rajasthan is the second largest producer of polyester fibre in India. The Pali and Bhilwara District produces more cloth than Bhiwandi, Maharashtra and the bhilwara is the largest city in suitings production and export and Pali is largest city in cotton and polyster in blouse pieces and rubia production and export. Several prominent chemical and engineering companies are located in the city of Kota, in southern Rajasthan. Rajasthan is pre-eminent in quarrying and mining in India. The Taj Mahal was built from the white marble which was mined from a town called Makrana. The state is the second largest source of cement in India. It has rich salt deposits at Sambhar, copper mines at Khetri, Jhunjhunu, and zinc mines at Dariba, Zawar mines and Rampura Aghucha (opencast) near Bhilwara. Dimensional stone mining is also undertaken in Rajasthan. Jodhpur sandstone is mostly used in monuments, important buildings and residential buildings. This stone is termed as "chittar patthar". Jodhpur leads in Handicraft and Guar Gum industry. Rajasthan is also a part of the Mumbai-Delhi Industrial corridor is set to benefit economically. The State gets 39% of the DMIC, with major districts of Jaipur, Alwar, Kota and Bhilwara benefiting.
Is there an answer to this question: What is the largest city for polyster blouse pieces in Rajasthan?

Answer: Pali is largest city in cotton and polyster in blouse pieces


Question: The most common symptom of LED (and diode laser) failure is the gradual lowering of light output and loss of efficiency. Sudden failures, although rare, can also occur. Early red LEDs were notable for their short service life. With the development of high-power LEDs the devices are subjected to higher junction temperatures and higher current densities than traditional devices. This causes stress on the material and may cause early light-output degradation. To quantitatively classify useful lifetime in a standardized manner it has been suggested to use L70 or L50, which are the runtimes (typically given in thousands of hours) at which a given LED reaches 70% and 50% of initial light output, respectively.
Is there an answer to this question: What could cause early light-output degradation in LEDs?

Answer:
higher junction temperatures