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In the first half of the twentieth century, almost all elevators had no automatic positioning of the floor on which the cab would stop. Some of the older freight elevators were controlled by switches operated by pulling on adjacent ropes. In general, most elevators before WWII were manually controlled by elevator operators using a rheostat connected to the motor. This rheostat (see picture) was enclosed within a cylindrical container about the size and shape of a cake. This was mounted upright or sideways on the cab wall and operated via a projecting handle, which was able to slide around the top half of the cylinder.
How were most elevators built before 1939 powered?
A: by elevator operators using a rheostat connected to the motor

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Selenizza is mainly used as an additive in the road construction sector. It is mixed with traditional bitumen to improve both the viscoelastic properties and the resistance to ageing. It may be blended with the hot bitumen in tanks, but its granular form allows it to be fed in the mixer or in the recycling ring of normal asphalt plants. Other typical applications include the production of mastic asphalts for sidewalks, bridges, car-parks and urban roads as well as drilling fluid additives for the oil and gas industry. Selenizza is available in powder or in granular material of various particle sizes and is packaged in big bags or in thermal fusible polyethylene bags.
What is Selenizza mixed with to improve resistance to bridges?
A: unanswerable

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Throughout the 14th century, French kings sought to expand their influence at the expense of the territorial holdings of the nobility. They ran into difficulties when attempting to confiscate the holdings of the English kings in southern France, leading to the Hundred Years' War, waged from 1337 to 1453. Early in the war the English under Edward III (r. 132777) and his son Edward, the Black Prince (d. 1376),[AF] won the battles of Crecy and Poitiers, captured the city of Calais, and won control of much of France.[AG] The resulting stresses almost caused the disintegration of the French kingdom during the early years of the war. In the early 15th century, France again came close to dissolving, but in the late 1420s the military successes of Joan of Arc (d. 1431) led to the victory of the French and the capture of the last English possessions in southern France in 1453. The price was high, as the population of France at the end of the Wars was likely half what it had been at the start of the conflict. Conversely, the Wars had a positive effect on English national identity, doing much to fuse the various local identities into a national English ideal. The conflict with France also helped create a national culture in England separate from French culture, which had previously been the dominant influence. The dominance of the English longbow began during early stages of the Hundred Years' War, and cannon appeared on the battlefield at Crecy in 1346.
What decade saw the victories of Joan of Arc?
A: 1420s

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Montana has a larger Native American population numerically and percentage-wise than most U.S. states. Although the state ranked 45th in population (according to the 2010 U.S. Census), it ranked 19th in total native people population. Native people constituted 6.5 percent of the state's total population, the sixth highest percentage of all 50 states. Montana has three counties in which Native Americans are a majority: Big Horn, Glacier, and Roosevelt. Other counties with large Native American populations include Blaine, Cascade, Hill, Missoula, and Yellowstone counties. The state's Native American population grew by 27.9 percent between 1980 and 1990 (at a time when Montana's entire population rose just 1.6 percent), and by 18.5 percent between 2000 and 2010. As of 2009, almost two-thirds of Native Americans in the state live in urban areas. Of Montana's 20 largest cities, Polson (15.7 percent), Havre (13.0 percent), Great Falls (5.0 percent), Billings (4.4 percent), and Anaconda (3.1 percent) had the greatest percentage of Native American residents in 2010. Billings (4,619), Great Falls (2,942), Missoula (1,838), Havre (1,210), and Polson (706) have the most Native Americans living there. The state's seven reservations include more than twelve distinct Native American ethnolinguistic groups.
What three counties are Native Americans a majority?
A:
Big Horn, Glacier, and Roosevelt