Input: Read this: Nevertheless, the ethno-geographic caste hierarchy favoring the Mongols and other ethnicities were accorded higher status than the Han Chinese majority. Although Han Chinese who were recruited as advisers were often actually more influential than high officials, their status was not as well defined. Kublai also abolished the imperial examinations of China's civil service legacy, which was not reinstated until Ayurbarwada Buyantu Khan's reign (1311–1320). Rossabi writes that Kublai recognized that in order to rule China, "he had to employ Chinese advisors and officials, yet he could not rely totally on Chinese advisers because he had to maintain a delicate balancing act between ruling the sedentary civilization of China and preserving the cultural identity and values of the Mongols." And "in governing China, he was concerned with the interests of his Chinese subjects, but also with exploiting the resources of the empire for his own aggrandizement. His motivations and objectives alternated from one to the other throughout his reign," according to Rossabi. Van Praag writes in The Status of Tibet that the Tibetans and Mongols, on the other hand, upheld a dual system of rule and an interdependent relationship that legitimated the succession of Mongol khans as universal Buddhist rulers, or chakravartin. Van Praag writes that "Tibet remained a unique part of the Empire and was never fully integrated into it," citing examples such as a licensed border market that existed between China and Tibet during the Yuan.
Question: When did Ayurbarwada Buyantu Khan reign?

Output: 1311–1320


Input: Read this: In April 1979, young students protested against Bokassa's decree that all school attendees would need to buy uniforms from a company owned by one of his wives. The government violently suppressed the protests, killing 100 children and teenagers. Bokassa himself may have been personally involved in some of the killings. In September 1979, France overthrew Bokassa and "restored" Dacko to power (subsequently restoring the name of the country to the Central African Republic). Dacko, in turn, was again overthrown in a coup by General André Kolingba on 1 September 1981.
Question: Who did General Andre protest against in April 1979?

Output: unanswerable


Input: Read this: But in statistical mechanics things get more complicated. On one hand, statistical mechanics is far superior to classical thermodynamics, in that thermodynamic behavior, such as glass breaking, can be explained by the fundamental laws of physics paired with a statistical postulate. But statistical mechanics, unlike classical thermodynamics, is time-reversal symmetric. The second law of thermodynamics, as it arises in statistical mechanics, merely states that it is overwhelmingly likely that net entropy will increase, but it is not an absolute law.
Question: What type of mechanics help to simplify things?

Output: unanswerable


Input: Read this: In 1854 president Antonio López de Santa Anna enlarged the area of the Federal District almost eightfold from the original 220 to 1,700 km2 (80 to 660 sq mi), annexing the rural and mountainous areas to secure the strategic mountain passes to the south and southwest to protect the city in event of a foreign invasion. (The Mexican–American War had just been fought.) The last changes to the limits of the Federal District were made between 1898 and 1902, reducing the area to the current 1,479 km2 (571 sq mi) by adjusting the southern border with the state of Morelos. By that time, the total number of municipalities within the Federal District was twenty-two.
Question: What is the current area of Mexico City?

Output:
1,479 km2 (571 sq mi)