Input: Read this: It is speculated by some archaeologists that Sumerian speakers were farmers who moved down from the north, after perfecting irrigation agriculture there. The Ubaid pottery of southern Mesopotamia has been connected via Choga Mami transitional ware to the pottery of the Samarra period culture (c. 5700 4900 BC C-14) in the north, who were the first to practice a primitive form of irrigation agriculture along the middle Tigris River and its tributaries. The connection is most clearly seen at Tell Awayli (Oueilli, Oueili) near Larsa, excavated by the French in the 1980s, where eight levels yielded pre-Ubaid pottery resembling Samarran ware. According to this theory, farming peoples spread down into southern Mesopotamia because they had developed a temple-centered social organization for mobilizing labor and technology for water control, enabling them to survive and prosper in a difficult environment.[citation needed]
Question: Who perfected irrigation in the south of Mesopotamia?

Output: unanswerable

Input: Read this: Since 1996, they have been archiving cached pages of web sites onto their large cluster of Linux nodes. They revisit sites every few weeks or months and archive a new version if the content has changed. Sites can also be captured on the fly by visitors who are offered a link to do so. The intent is to capture and archive content that otherwise would be lost whenever a site is changed or closed down. Their grand vision is to archive the entire Internet.
Question: What is the ultimate aim of the visitors?

Output: unanswerable

Input: Read this: Other trees of note include the royal palm, sea grape trees in the form of shrubs on the beaches and as 5 to 7 m trees in the interior areas of the island, aloe or aloe vera (brought from the Mediterranean), the night blooming cereus, mamillaria nivosa, yellow prickly pear or barbary fig which was planted as barbed wire defences against invading British army in 1773, Mexican cactus, stapelia gigantea, golden trumpet or yellow bell which was originally from South America, bougainvillea and others.
Question: In what year was aloe vera brought to St. Barts from the Mediterranean?

Output: unanswerable

Input: Read this: Despite competition from other materials, copper remains the preferred electrical conductor in nearly all categories of electrical wiring with the major exception being overhead electric power transmission where aluminium is often preferred. Copper wire is used in power generation, power transmission, power distribution, telecommunications, electronics circuitry, and countless types of electrical equipment. Electrical wiring is the most important market for the copper industry. This includes building wire, communications cable, power distribution cable, appliance wire, automotive wire and cable, and magnet wire. Roughly half of all copper mined is used to manufacture electrical wire and cable conductors. Many electrical devices rely on copper wiring because of its multitude of inherent beneficial properties, such as its high electrical conductivity, tensile strength, ductility, creep (deformation) resistance, corrosion resistance, low thermal expansion, high thermal conductivity, solderability, and ease of installation.
Question: What is the most important market for copper today?

Output:
Electrical wiring