Problem: War on Terror:

On 12 January 2002, Musharraf gave a speech against Islamic extremism. He unequivocally condemned all acts of terrorism and pledged to combat Islamic extremism and lawlessness within Pakistan itself. He stated that his government was committed to rooting out extremism and made it clear that the banned militant organizations would not be allowed to resurface under any new name. He said, "the recent decision to ban extremist groups promoting militancy was taken in the national interest after thorough consultations. It was not taken under any foreign influence".

What was extremism committed to rooting out?
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A: unanswerable

Problem: Gothic architecture:

In England, partly in response to a philosophy propounded by the Oxford Movement and others associated with the emerging revival of 'high church' or Anglo-Catholic ideas during the second quarter of the 19th century, neo-Gothic began to become promoted by influential establishment figures as the preferred style for ecclesiastical, civic and institutional architecture. The appeal of this Gothic revival (which after 1837, in Britain, is sometimes termed Victorian Gothic), gradually widened to encompass "low church" as well as "high church" clients. This period of more universal appeal, spanning 18551885, is known in Britain as High Victorian Gothic.

What other style of architecture did influential figures of the 14th century prefer to use Victorian Gothic for?
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A: unanswerable

Problem: Electric motor:

Large brushes are desired for a larger brush contact area to maximize motor output, but small brushes are desired for low mass to maximize the speed at which the motor can run without the brushes excessively bouncing and sparking. (Small brushes are also desirable for lower cost.) Stiffer brush springs can also be used to make brushes of a given mass work at a higher speed, but at the cost of greater friction losses (lower efficiency) and accelerated brush and commutator wear. Therefore, DC motor brush design entails a trade-off between output power, speed, and efficiency/wear.

How can the speed of larger brushes be increased?
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A: Stiffer brush springs

Problem: Geological history of Earth:

A global drop in sea level at the end of the Devonian reversed early in the Carboniferous; this created the widespread epicontinental seas and carbonate deposition of the Mississippian. There was also a drop in south polar temperatures; southern Gondwana was glaciated throughout the period, though it is uncertain if the ice sheets were a holdover from the Devonian or not. These conditions apparently had little effect in the deep tropics, where lush coal swamps flourished within 30 degrees of the northernmost glaciers. A mid-Carboniferous drop in sea-level precipitated a major marine extinction, one that hit crinoids and ammonites especially hard. This sea-level drop and the associated unconformity in North America separate the Mississippian Period from the Pennsylvanian period.

The Pennsylvania period is separated by the drop in Carboniferous era sea levels from what other period?
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A:
Mississippian Period