Problem: Given the question: Extract the answer to the question from the following context. Question: How does this work in practice? Context: A servo system differs from some stepper motor applications in that the position feedback is continuous while the motor is running; a stepper system relies on the motor not to "miss steps" for short term accuracy, although a stepper system may include a "home" switch or other element to provide long-term stability of control. For instance, when a typical dot matrix computer printer starts up, its controller makes the print head stepper motor drive to its left-hand limit, where a position sensor defines home position and stops stepping. As long as power is on, a bidirectional counter in the printer's microprocessor keeps track of print-head position.
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The answer is:
As long as power is on, a bidirectional counter in the printer's microprocessor keeps track of print-head position

Problem: Given the question: Extract the answer to the question from the following context. Question: What sparked problems? Context: Concerns have often been raised over the buying public's moral complicity in purchasing products assembled or otherwise manufactured in developing countries with child labour. However, others have raised concerns that boycotting products manufactured through child labour may force these children to turn to more dangerous or strenuous professions, such as prostitution or agriculture. For example, a UNICEF study found that after the Child Labour Deterrence Act was introduced in the US, an estimated 50,000 children were dismissed from their garment industry jobs in Bangladesh, leaving many to resort to jobs such as "stone-crushing, street hustling, and prostitution", jobs that are "more hazardous and exploitative than garment production". The study suggests that boycotts are "blunt instruments with long-term consequences, that can actually harm rather than help the children involved."
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The answer is:
the buying public's moral complicity in purchasing products assembled or otherwise manufactured in developing countries with child labour

Problem: Given the question: Extract the answer to the question from the following context. Question: what is the last nature formation mentioned? Context: On Earth, 99% of glacial ice is contained within vast ice sheets in the polar regions, but glaciers may be found in mountain ranges on every continent except Australia, and on a few high-latitude oceanic islands. Between 35N and 35S, glaciers occur only in the Himalayas, Andes, Rocky Mountains, a few high mountains in East Africa, Mexico, New Guinea and on Zard Kuh in Iran. Glaciers cover about 10 percent of Earth's land surface. Continental glaciers cover nearly 13,000,000 km2 (510^6 sq mi) or about 98 percent of Antarctica's 13,200,000 km2 (5.110^6 sq mi), with an average thickness of 2,100 m (7,000 ft). Greenland and Patagonia also have huge expanses of continental glaciers.
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The answer is:
glaciers