Problem: Sahara:

The effects of local surface low pressure are extremely limited because upper-level subsidence still continues to block any form of air ascent. Also, to be protected against rain-bearing weather systems by the atmospheric circulation itself, the desert is made even drier by his geographical configuration and location. Indeed, the extreme aridity of the Sahara can't be only explained by the subtropical high pressure. The Atlas Mountains, found in Algeria, Morocco and Tunisia also help to enhance the aridity of the northern part of the desert. These major mountain ranges act as a barrier causing a strong rain shadow effect on the leeward side by dropping much of the humidity brought by atmospheric disturbances along the polar front which affects the surrounding Mediterranean climates.

what is blocked buy the surface low pressure?
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A: unanswerable

Problem: After two forays into more serious dramatic films, Spielberg then directed the third Indiana Jones film, 1989's Indiana Jones and the Last Crusade. Once again teaming up with Lucas and Ford, Spielberg also cast actor Sean Connery in a supporting role as Indy's father. The film earned generally positive reviews and was another box office success, becoming the highest grossing film worldwide that year; its total box office receipts even topped those of Tim Burton's much-anticipated film Batman, which had been the bigger hit domestically. Also in 1989, he re-united with actor Richard Dreyfuss for the romantic comedy-drama Always, about a daredevil pilot who extinguishes forest fires. Spielberg's first romantic film, Always was only a moderate success and had mixed reviews.
Who played Indiana Jones's father?
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Answer: Sean Connery

Q: What is a question about this article? If the question is unanswerable, say "unanswerable".
In Europe and Australia, the system was released to two separate marketing regions. One region consisted of most of mainland Europe (excluding Italy), and distribution there was handled by a number of different companies, with Nintendo responsible for most cartridge releases. Most of this region saw a 1986 release. Mattel handled distribution for the other region, consisting of the United Kingdom, Ireland, Canada, Italy, Australia and New Zealand, starting the following year. Not until the 1990s did Nintendo's newly created European branch direct distribution throughout Europe.
Who released cartridges in mainland Europe?
A: Nintendo

Context and question: World literature was enriched by the works of Edmund Spenser, John Milton, John Bunyan, John Donne, John Dryden, Daniel Defoe, William Wordsworth, Jonathan Swift, Johann Wolfgang Goethe, Friedrich Schiller, Samuel Taylor Coleridge, Edgar Allan Poe, Matthew Arnold, Conrad Ferdinand Meyer, Theodor Fontane, Washington Irving, Robert Browning, Emily Dickinson, Emily Bronte, Charles Dickens, Nathaniel Hawthorne, Thomas Stearns Eliot, John Galsworthy, Thomas Mann, William Faulkner, John Updike, and many others.
Edgar Allen Poe added value to literature in what area?
Answer: World

Question: Because of the magnitude of the quake, and the media attention on China, foreign nations and organizations immediately responded to the disaster by offering condolences and assistance. On May 14, UNICEF reported that China formally requested the support of the international community to respond to the needs of affected families.
Is there an answer to this question: Why did the world community notice the need for help?

Answer: magnitude of the quake

Annelids with blood vessels use metanephridia to remove soluble waste products, while those without use protonephridia. Both of these systems use a two-stage filtration process, in which fluid and waste products are first extracted and these are filtered again to re-absorb any re-usable materials while dumping toxic and spent materials as urine. The difference is that protonephridia combine both filtration stages in the same organ, while metanephridia perform only the second filtration and rely on other mechanisms for the first in annelids special filter cells in the walls of the blood vessels let fluids and other small molecules pass into the coelomic fluid, where it circulates to the metanephridia. In annelids the points at which fluid enters the protonephridia or metanephridia are on the forward side of a septum while the second-stage filter and the nephridiopore (exit opening in the body wall) are in the following segment. As a result, the hindmost segment (before the growth zone and pygidium) has no structure that extracts its wastes, as there is no following segment to filter and discharge them, while the first segment contains an extraction structure that passes wastes to the second, but does not contain the structures that re-filter and discharge urine.
If it is possible to answer this question, answer it for me (else, reply "unanswerable"): How many stages are there in annelids' waste filtration?
Ah, so..
two