Problem: Solar energy:

Agriculture and horticulture seek to optimize the capture of solar energy in order to optimize the productivity of plants. Techniques such as timed planting cycles, tailored row orientation, staggered heights between rows and the mixing of plant varieties can improve crop yields. While sunlight is generally considered a plentiful resource, the exceptions highlight the importance of solar energy to agriculture. During the short growing seasons of the Little Ice Age, French and English farmers employed fruit walls to maximize the collection of solar energy. These walls acted as thermal masses and accelerated ripening by keeping plants warm. Early fruit walls were built perpendicular to the ground and facing south, but over time, sloping walls were developed to make better use of sunlight. In 1699, Nicolas Fatio de Duillier even suggested using a tracking mechanism which could pivot to follow the Sun. Applications of solar energy in agriculture aside from growing crops include pumping water, drying crops, brooding chicks and drying chicken manure. More recently the technology has been embraced by vinters, who use the energy generated by solar panels to power grape presses.

What was the purpose of the fruit walls built by French and English farmers?
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A: acted as thermal masses and accelerated ripening by keeping plants warm


Problem: The Canton of Bern school system provides one year of non-obligatory kindergarten, followed by six years of primary school. This is followed by three years of obligatory lower secondary school where the pupils are separated according to ability and aptitude. Following the lower secondary pupils may attend additional schooling or they may enter an apprenticeship.
What seperates the children in secondary school?
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Answer: ability and aptitude


Q: What is a question about this article? If the question is unanswerable, say "unanswerable".
Southeastern Pennsylvania was assigned the 215 area code in 1947 when the North American Numbering Plan of the "Bell System" went into effect. The geographic area covered by the code was split nearly in half in 1994 when area code 610 was created, with the city and its northern suburbs retaining 215. Overlay area code 267 was added to the 215 service area in 1997, and 484 was added to the 610 area in 1999. A plan in 2001 to introduce a third overlay code to both service areas (area code 445 to 215, area code 835 to 610) was delayed and later rescinded.
When was the 610 area code added?
A: 1994


Context and question: The constitution of Jordan grants its monarch the right to withhold assent to laws passed by its parliament. Article 93 of that document gives the Jordanian sovereign six months to sign or veto any legislation sent to him from the National Assembly; if he vetoes it within that timeframe, the assembly may override his veto by a two-thirds vote of both houses; otherwise, the law does not go into effect (but it may be reconsidered in the next session of the assembly). If the monarch fails to act within six months of the bill being presented to him, it becomes law without his signature.
What happens if the soverign doesn't sign the bill within the six-month time frame?
Answer: , it becomes law without his signature


Question: With limited resources Muawiyah went about creating allies. Muawiyah married Maysum the daughter of the chief of the Kalb tribe, that was a large Jacobite Christian Arab tribe in Syria. His marriage to Maysum was politically motivated. The Kalb tribe had remained largely neutral when the Muslims first went into Syria. After the plague that killed much of the Muslim Army in Syria, by marrying Maysum, Muawiyah started to use the Jacobite Christians, against the Romans. Muawiya's wife Maysum (Yazid's mother) was also a Jacobite Christian. With limited resources and the Byzantine just over the border, Muawiyah worked in cooperation with the local Christian population. To stop Byzantine harassment from the sea during the Arab-Byzantine Wars, in 649 Muawiyah set up a navy; manned by Monophysitise Christians, Copts and Jacobite Syrian Christians sailors and Muslim troops.
Is there an answer to this question: What tribe did Muawiyah's wife belong to?

Answer: Kalb


The roots of Presbyterianism lie in the European Reformation of the 16th century; the example of John Calvin's Geneva being particularly influential. Most Reformed churches which trace their history back to Scotland are either presbyterian or congregationalist in government. In the twentieth century, some Presbyterians played an important role in the ecumenical movement, including the World Council of Churches. Many Presbyterian denominations have found ways of working together with other Reformed denominations and Christians of other traditions, especially in the World Communion of Reformed Churches. Some Presbyterian churches have entered into unions with other churches, such as Congregationalists, Lutherans, Anglicans, and Methodists. Presbyterians in the United States came largely from Scotch-Irish immigrants communities, and also from New England Yankee communities that had originally been Congregational but changed because of an agreed-upon "Plan of Union of 1801" for frontier areas.
If it is possible to answer this question, answer it for me (else, reply "unanswerable"): Where do most presbyterian churches trace their history back to?
Ah, so..
Scotland