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The top 50 m (160 ft) of a glacier are rigid because they are under low pressure. This upper section is known as the fracture zone and moves mostly as a single unit over the plastically flowing lower section. When a glacier moves through irregular terrain, cracks called crevasses develop in the fracture zone. Crevasses form due to differences in glacier velocity. If two rigid sections of a glacier move at different speeds and directions, shear forces cause them to break apart, opening a crevasse. Crevasses are seldom more than 46 m (150 ft) deep but in some cases can be 300 m (1,000 ft) or even deeper. Beneath this point, the plasticity of the ice is too great for cracks to form. Intersecting crevasses can create isolated peaks in the ice, called seracs.
Why is the lower 50m of a glacier rigid?
A: unanswerable

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By the mid-7th century, English and Irish missionaries set out to convert the Frisians. The pope appointed their leader, Willibrordus, bishop of the Frisians. The tenure of Willibrordus is generally considered to be the beginning of the Bishopric of Utrecht. In 723, the Frankish leader Charles Martel bestowed the fortress in Utrecht and the surrounding lands as the base of the bishops. From then on Utrecht became one of the most influential seats of power for the Roman Catholic Church in the Netherlands. The archbishops of Utrecht were based at the uneasy northern border of the Carolingian Empire. In addition, the city of Utrecht had competition from the nearby trading centre Dorestad. After the fall of Dorestad around 850, Utrecht became one of the most important cities in the Netherlands. The importance of Utrecht as a centre of Christianity is illustrated by the election of the Utrecht-born Adriaan Florenszoon Boeyens as pope in 1522 (the last non-Italian pope before John Paul II).
Who did the pope appoint Bishop
A: The pope appointed their leader, Willibrordus, bishop of the Frisians

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Cotton remained a key crop in the Southern economy after emancipation and the end of the Civil War in 1865. Across the South, sharecropping evolved, in which landless black and white farmers worked land owned by others in return for a share of the profits. Some farmers rented the land and bore the production costs themselves. Until mechanical cotton pickers were developed, cotton farmers needed additional labor to hand-pick cotton. Picking cotton was a source of income for families across the South. Rural and small town school systems had split vacations so children could work in the fields during "cotton-picking."
What function of southern schools was created for children to pick cotton?
A: split vacations

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The northern group consists of the keskmurre or central dialect that is also the basis for the standard language, the läänemurre or western dialect, roughly corresponding to Läänemaa and Pärnumaa, the saarte murre (islands') dialect of Saaremaa and Hiiumaa and the idamurre or eastern dialect on the northwestern shore of Lake Peipsi.
What is the dialect from Lake Peipsi?
A:
the idamurre or eastern dialect