Input: Read this: There are a number of proposals to redefine certain of the SI base units in terms of fundamental physical constants. This has already been done for the metre, which is defined in terms of a fixed value of the speed of light. The most urgent unit on the list for redefinition is the kilogram, whose value has been fixed for all science (since 1889) by the mass of a small cylinder of platinumiridium alloy kept in a vault just outside Paris. While nobody knows if the mass of the International Prototype Kilogram has changed since 1889 the value 1 kg of its mass expressed in kilograms is by definition unchanged and therein lies one of the problems it is known that over such a timescale the many similar PtIr alloy cylinders kept in national laboratories around the world, have changed their relative mass by several tens of parts per million, however carefully they are stored, and the more so the more they have been taken out and used as mass standards. A change of several tens of micrograms in one kilogram is equivalent to the current uncertainty in the value of the Planck constant in SI units.
Question: What is the shape of the object that establishes the base unit of the kilometer?

Output: unanswerable

Input: Read this: The United States shares land borders with Canada (to the north) and Mexico (to the south), and a territorial water border with Russia in the northwest, and two territorial water borders in the southeast between Florida and Cuba, and Florida and the Bahamas. The contiguous forty-eight states are otherwise bounded by the Pacific Ocean on the west, the Atlantic Ocean on the east, and the Gulf of Mexico to the southeast. Alaska borders the Pacific Ocean to the south, the Bering Strait to the west, and the Arctic Ocean to the north, while Hawaii lies far to the southwest of the mainland in the Pacific Ocean.
Question: The Gulf of Mexico lies to the southwest of what country?

Output: unanswerable

Input: Read this: Proto-Slavic, sometimes referred to as Common Slavic or Late Proto-Slavic, is defined as the last stage of the language preceding the geographical split of the historical Slavic languages. That language was uniform, and on the basis of borrowings from foreign languages and Slavic borrowings into other languages, cannot be said to have any recognizable dialects, suggesting a comparatively compact homeland. Slavic linguistic unity was to some extent visible as late as Old Church Slavonic manuscripts which, though based on local Slavic speech of Thessaloniki, could still serve the purpose of the first common Slavic literary language.
Question: What is another term for Old Church Slavonic?

Output: unanswerable

Input: Read this: South Tucson is actually the name of an independent, incorporated town of 1 sq mi (2.6 km2), completely surrounded by the city of Tucson, sitting just south of downtown. South Tucson has a colorful, dynamic history. It was first incorporated in 1936, and later reincorporated in 1940. The population consists of about 83% Mexican-American and 10% Native American residents. South Tucson is widely known for its many Mexican restaurants and the architectural styles which include bright outdoor murals, many of which have been painted over due to city policy.
Question: When was South Tucson reincorporated?

Output:
1940