Problem: Copper:

Together with caesium and gold (both yellow), and osmium (bluish), copper is one of only four elemental metals with a natural color other than gray or silver. Pure copper is orange-red and acquires a reddish tarnish when exposed to air. The characteristic color of copper results from the electronic transitions between the filled 3d and half-empty 4s atomic shells the energy difference between these shells is such that it corresponds to orange light. The same mechanism accounts for the yellow color of gold and caesium.

What color is fake copper?
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A: unanswerable

Problem: In July 2015, Eton accidentally sent emails to 400 prospective students, offering them conditional entrance to the school in September 2017. The email was intended for nine students, but an IT glitch caused the email to be sent to 400 additional families, who didn't necessarily have a place. In response, the school issued the following statement: "This error was discovered within minutes and each family was immediately contacted to notify them that it should be disregarded and to apologise. We take this type of incident very seriously indeed and so a thorough investigation, overseen by the headmaster Tony Little and led by the tutor for admissions, is being carried out to find out exactly what went wrong and ensure it cannot happen again. Eton College offers its sincere apologies to those boys concerned and their families. We deeply regret the confusion and upset this must have caused."
How many prospective students received a mistaken email in July 2015?
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Answer: 400

Q: What is a question about this article? If the question is unanswerable, say "unanswerable".
GE (General Electric) Energy's renewable energy business has expanded greatly, to keep up with growing U.S. and global demand for clean energy. Since entering the renewable energy industry in 2002, GE has invested more than $850 million in renewable energy commercialization. In August 2008 it acquired Kelman Ltd, a Northern Ireland company specializing in advanced monitoring and diagnostics technologies for transformers used in renewable energy generation, and announced an expansion of its business in Northern Ireland in May 2010. In 2009, GE's renewable energy initiatives, which include solar power, wind power and GE Jenbacher gas engines using renewable and non-renewable methane-based gases, employ more than 4,900 people globally and have created more than 10,000 supporting jobs.
As of 2009, how many people did GE employ in its renewable energy initiatives?
A: more than 4,900

Context and question: Zinc metal is produced using extractive metallurgy. After grinding the ore, froth flotation, which selectively separates minerals from gangue by taking advantage of differences in their hydrophobicity, is used to get an ore concentrate. This concentrate consists of about 50% zinc with the rest being sulfur (32%), iron (13%), and SiO
2 (5%). The composition of this is normally zinc sulfide (80% to 85%), iron sulfide (7.0% to 12%), lead sulfide (3.0% to 5.0%) silica (2.5% to 3.5%), and cadmium sulfide (0.35% to 0.41%).
What is froth flotation no longer used for?
Answer: unanswerable

Question: After Charles II of England (16301685) was restored to the English throne in 1660 following Oliver Cromwell's Protectorate, he granted the chartered Province of Carolina to eight of his loyal friends, known as the Lords Proprietors, on March 24, 1663. It took seven years before the group arranged for settlement expeditions. The first of these founded Charles Town, in 1670. Governance, settlement, and development were to follow a visionary plan known as the Grand Model prepared for the Lords Proprietors by John Locke.
Is there an answer to this question: When was Charles I of England restored to the throne?

Answer: unanswerable

In 941, Igor led another major Rus' attack on Constantinople, probably over trading rights again. A navy of 10,000 vessels, including Pecheneg allies, landed on the Bithynian coast and devastated the Asiatic shore of the Bosphorus. The attack was well-timed, perhaps due to intelligence, as the Byzantine fleet was occupied with the Arabs in the Mediterranean, and the bulk of its army was stationed in the east. The Rus' burned towns, churches, and monasteries, butchering the people and amassing booty. The emperor arranged for a small group of retired ships to be outfitted with Greek fire throwers and sent them out to meet the Rus', luring them into surrounding the contingent before unleashing the Greek fire. Liutprand of Cremona wrote that "the Rus', seeing the flames, jumped overboard, preferring water to fire. Some sank, weighed down by the weight of their breastplates and helmets; others caught fire." Those captured were beheaded. The ploy dispelled the Rus' fleet, but their attacks continued into the hinterland as far as Nicomedia, with many atrocities reported as victims were crucified and set up for use as targets. At last a Byzantine army arrived from the Balkans to drive the Rus' back, and a naval contingent reportedly destroyed much of the Rus' fleet on its return voyage (possibly an exaggeration since the Rus' soon mounted another attack). The outcome indicates increased military might by Byzantium since 911, suggesting a shift in the balance of power.
If it is possible to answer this question, answer it for me (else, reply "unanswerable"): What year was the Rus fleet defeated?
Ah, so..
unanswerable