Problem: Annelid:

Charles Darwin's book The Formation of Vegetable Mould through the Action of Worms (1881) presented the first scientific analysis of earthworms' contributions to soil fertility. Some burrow while others live entirely on the surface, generally in moist leaf litter. The burrowers loosen the soil so that oxygen and water can penetrate it, and both surface and burrowing worms help to produce soil by mixing organic and mineral matter, by accelerating the decomposition of organic matter and thus making it more quickly available to other organisms, and by concentrating minerals and converting them to forms that plants can use more easily. Earthworms are also important prey for birds ranging in size from robins to storks, and for mammals ranging from shrews to badgers, and in some cases conserving earthworms may be essential for conserving endangered birds.

How does burrowers' loosening help the soil?
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A: oxygen and water can penetrate it

Problem: On 14 May 1955, the USSR and other seven European countries "reaffirming their desire for the establishment of a system of European collective security based on the participation of all European states irrespective of their social and political systems" established the Warsaw Pact in response to the integration of the Federal Republic of Germany into NATO, declaring that: "a remilitarized Western Germany and the integration of the latter in the North-Atlantic bloc [...] increase the danger of another war and constitutes a threat to the national security of the peaceable states; [...] in these circumstances the peaceable European states must take the necessary measures to safeguard their security".
What pact was declared in May 1956?
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Answer: unanswerable

Q: What is a question about this article? If the question is unanswerable, say "unanswerable".
While the cardinalate has long been expanded beyond the Roman pastoral clergy and Roman Curia, every cardinal priest has a titular church in Rome, though they may be bishops or archbishops elsewhere, just as cardinal bishops are given one of the suburbicarian dioceses around Rome. Pope Paul VI abolished all administrative rights cardinals had with regard to their titular churches, though the cardinal's name and coat of arms are still posted in the church, and they are expected to celebrate mass and preach there if convenient when they are in Rome.
What has not been expanded beyond the Roman pastoral clergy and Roman Curia?
A: unanswerable

Context and question: The photoelectric effect is the emission of electrons (called "photoelectrons") from a surface when light is shone on it. It was first observed by Alexandre Edmond Becquerel in 1839, although credit is usually reserved for Heinrich Hertz, who published the first thorough investigation in 1887. Another particularly thorough investigation was published by Philipp Lenard in 1902. Einstein's 1905 paper discussing the effect in terms of light quanta would earn him the Nobel Prize in 1921, when his predictions had been confirmed by the experimental work of Robert Andrews Millikan. The Nobel committee awarded the prize for his work on the photo-electric effect, rather than relativity, both because of a bias against purely theoretical physics not grounded in discovery or experiment, and dissent amongst its members as to the actual proof that relativity was real.
When was the photoelectric effect first observed?
Answer: 1839

Question: The British 16th Air Assault Brigade (later reinforced by Royal Marines) formed the core of the force in southern Afghanistan, along with troops and helicopters from Australia, Canada and the Netherlands. The initial force consisted of roughly 3,300 British, 2,000 Canadian, 1,400 from the Netherlands and 240 from Australia, along with special forces from Denmark and Estonia and small contingents from other nations. The monthly supply of cargo containers through Pakistani route to ISAF in Afghanistan is over 4,000 costing around 12 billion in Pakistani Rupees.
Is there an answer to this question: How many Pakistanis were involved?

Answer: unanswerable

Copper occurs naturally as native copper and was known to some of the oldest civilizations on record. It has a history of use that is at least 10,000 years old, and estimates of its discovery place it at 9000 BC in the Middle East; a copper pendant was found in northern Iraq that dates to 8700 BC. There is evidence that gold and meteoric iron (but not iron smelting) were the only metals used by humans before copper. The history of copper metallurgy is thought to have followed the following sequence: 1) cold working of native copper, 2) annealing, 3) smelting, and 4) the lost wax method. In southeastern Anatolia, all four of these metallurgical techniques appears more or less simultaneously at the beginning of the Neolithic c. 7500 BC. However, just as agriculture was independently invented in several parts of the world, copper smelting was invented locally in several different places. It was probably discovered independently in China before 2800 BC, in Central America perhaps around 600 AD, and in West Africa about the 9th or 10th century AD. Investment casting was invented in 45004000 BC in Southeast Asia and carbon dating has established mining at Alderley Edge in Cheshire, UK at 2280 to 1890 BC. Otzi the Iceman, a male dated from 33003200 BC, was found with an axe with a copper head 99.7% pure; high levels of arsenic in his hair suggest his involvement in copper smelting. Experience with copper has assisted the development of other metals; in particular, copper smelting led to the discovery of iron smelting. Production in the Old Copper Complex in Michigan and Wisconsin is dated between 6000 and 3000 BC. Natural bronze, a type of copper made from ores rich in silicon, arsenic, and (rarely) tin, came into general use in the Balkans around 5500 BC.[citation needed]
If it is possible to answer this question, answer it for me (else, reply "unanswerable"): What type of material can't be produced?
Ah, so..
unanswerable