Problem: Copper:

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.

What metal are most overhead electrical wires made out of?
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A: aluminium


Problem: Three years later, as March 1865 ended, the Confederate capitol became indefensible. On March 25, Confederate General John B. Gordon's desperate attack on Fort Stedman east of Petersburg failed. On April 1, General Philip Sheridan, assigned to interdict the Southside Railroad, met brigades commanded by George Pickett at the Five Forks junction, smashing them, taking thousands of prisoners, and encouraging General Grant to order a general advance. When the Union Sixth Corps broke through Confederate lines on Boydton Plank Road south of Petersburg, Confederate casualties exceeded 5000, or about a tenth of Lee's defending army. General Lee then informed Jefferson Davis that he was about to evacuate Richmond.
Where was Petersburg located in relation to Ford Stedman?
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Answer: east


Q: What is a question about this article? If the question is unanswerable, say "unanswerable".
The San Diego Symphony at Symphony Towers performs on a regular basis and is directed by Jahja Ling. The San Diego Opera at Civic Center Plaza, directed by Ian Campbell, was ranked by Opera America as one of the top 10 opera companies in the United States. Old Globe Theatre at Balboa Park produces about 15 plays and musicals annually. The La Jolla Playhouse at UCSD is directed by Christopher Ashley. Both the Old Globe Theatre and the La Jolla Playhouse have produced the world premieres of plays and musicals that have gone on to win Tony Awards or nominations on Broadway. The Joan B. Kroc Theatre at Kroc Center's Performing Arts Center is a 600-seat state-of-the-art theatre that hosts music, dance, and theatre performances. The San Diego Repertory Theatre at the Lyceum Theatres in Horton Plaza produces a variety of plays and musicals. Hundreds of movies and a dozen TV shows have been filmed in San Diego, a tradition going back as far as 1898.
What did Opera America call the San Diego Opera at the Civic Center Plaza?
A: one of the top 10 opera companies in the United States


Context and question: Estonian has been influenced by Swedish, German (initially Middle Low German, which was the lingua franca of the Hanseatic League and spoken natively in the territories of what is today known as Estonia by a sizeable burgher community of Baltic Germans, later Estonian was also influenced by standard German), and Russian, though it is not related to them genetically.
Baltic Germans spoke which language? 
Answer: unanswerable


Question: A "tag" in an audio file is a section of the file that contains metadata such as the title, artist, album, track number or other information about the file's contents. The MP3 standards do not define tag formats for MP3 files, nor is there a standard container format that would support metadata and obviate the need for tags.
Is there an answer to this question: What would be needed to support metadata and obviate the need for tags?

Answer: a standard container format


Problem: Flowering plant:

The botanical term "Angiosperm", from the Ancient Greek αγγείον, angeíon (bottle, vessel) and σπέρμα, (seed), was coined in the form Angiospermae by Paul Hermann in 1690, as the name of one of his primary divisions of the plant kingdom. This included flowering plants possessing seeds enclosed in capsules, distinguished from his Gymnospermae, or flowering plants with achenial or schizo-carpic fruits, the whole fruit or each of its pieces being here regarded as a seed and naked. The term and its antonym were maintained by Carl Linnaeus with the same sense, but with restricted application, in the names of the orders of his class Didynamia. Its use with any approach to its modern scope became possible only after 1827, when Robert Brown established the existence of truly naked ovules in the Cycadeae and Coniferae, and applied to them the name Gymnosperms.[citation needed] From that time onward, as long as these Gymnosperms were, as was usual, reckoned as dicotyledonous flowering plants, the term Angiosperm was used antithetically by botanical writers, with varying scope, as a group-name for other dicotyledonous plants.

Why did Robert Brown use the term dicotyledonous?
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A:
unanswerable