Problem: Nutrition:

Plants uptake essential elements from the soil through their roots and from the air (consisting of mainly nitrogen and oxygen) through their leaves. Green plants obtain their carbohydrate supply from the carbon dioxide in the air by the process of photosynthesis. Carbon and oxygen are absorbed from the air, while other nutrients are absorbed from the soil. Nutrient uptake in the soil is achieved by cation exchange, wherein root hairs pump hydrogen ions (H+) into the soil through proton pumps. These hydrogen ions displace cations attached to negatively charged soil particles so that the cations are available for uptake by the root. In the leaves, stomata open to take in carbon dioxide and expel oxygen. The carbon dioxide molecules are used as the carbon source in photosynthesis.

What part of the leaf in a plant takes in carbon dioxide and releases oxygen?
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A: stomata

Problem: Unfortunately for those who wanted or were required to wear green, there were no good vegetal green dyes which resisted washing and sunlight. Green dyes were made out of the fern, plantain, buckthorn berries, the juice of nettles and of leeks, the digitalis plant, the broom plant, the leaves of the fraxinus, or ash tree, and the bark of the alder tree, but they rapidly faded or changed color. Only in the 16th century was a good green dye produced, by first dyeing the cloth blue with woad, and then yellow with reseda luteola, also known as yellow-weed.
What color did green-dyed clothes often change to?
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Answer: unanswerable

Q: What is a question about this article? If the question is unanswerable, say "unanswerable".
On 14 June, while the world's attention was focused on the fall of Paris to Nazi Germany a day earlier, the Soviet military blockade on Estonia went into effect, two Soviet bombers downed the Finnish passenger aeroplane "Kaleva" flying from Tallinn to Helsinki carrying three diplomatic pouches from the US delegations in Tallinn, Riga and Helsinki. On 16 June, the Soviet Union invaded Estonia. The Red Army exited from their military bases in Estonia on 17 June. The following day, some 90,000 additional troops entered the country. In the face of overwhelming Soviet force, the Estonian government capitulated on 17 June 1940 to avoid bloodshed.
What capital of France was lost to the Nazi Germans?
A: Paris

Context and question: Although the Estonian orthography is generally guided by phonemic principles, with each grapheme corresponding to one phoneme, there are some historical and morphological deviations from this: for example preservation of the morpheme in declension of the word (writing b, g, d in places where p, k, t is pronounced) and in the use of 'i' and 'j'.[clarification needed] Where it is very impractical or impossible to type s and z, they are substituted with sh and zh in some written texts, although this is considered incorrect. Otherwise, the h in sh represents a voiceless glottal fricative, as in Pasha (pas-ha); this also applies to some foreign names.
On what occasions are s and z replaced with sh and zh?
Answer: Where it is very impractical or impossible to type s and z

Question: In 1964 Israel hosted and won the Asian Nations Cup; in 1970 the Israel national football team managed to qualify to the FIFA World Cup, which is still considered[by whom?] the biggest achievement of Israeli football.[citation needed] The 1974 Asian Games held in Tehran, were the last Asian Games in which Israel participated, and was plagued by the Arab countries which refused to compete with Israel, and Israel since ceased competing in Asian competitions. Israel was excluded from the 1978 Asian Games due to security and expense involved if they were to participate. In 1994, UEFA agreed to admit Israel and all Israeli sporting organizations now compete in Europe.[citation needed]
Is there an answer to this question: When did Israel host and win the Asian Nations Cup?

Answer: 1964

Q: What is a question about this article? If the question is unanswerable, say "unanswerable".
Codd's paper was picked up by two people at Berkeley, Eugene Wong and Michael Stonebraker. They started a project known as INGRES using funding that had already been allocated for a geographical database project and student programmers to produce code. Beginning in 1973, INGRES delivered its first test products which were generally ready for widespread use in 1979. INGRES was similar to System R in a number of ways, including the use of a "language" for data access, known as QUEL. Over time, INGRES moved to the emerging SQL standard.
When was INGRES first tested?
A:
1973