Problem: Film speed:

Film speed is used in the exposure equations to find the appropriate exposure parameters. Four variables are available to the photographer to obtain the desired effect: lighting, film speed, f-number (aperture size), and shutter speed (exposure time). The equation may be expressed as ratios, or, by taking the logarithm (base 2) of both sides, by addition, using the APEX system, in which every increment of 1 is a doubling of exposure; this increment is commonly known as a "stop". The effective f-number is proportional to the ratio between the lens focal length and aperture diameter, the diameter itself being proportional to the square root of the aperture area. Thus, a lens set to f/1.4 allows twice as much light to strike the focal plane as a lens set to f/2. Therefore, each f-number factor of the square root of two (approximately 1.4) is also a stop, so lenses are typically marked in that progression: f/1.4, 2, 2.8, 4, 5.6, 8, 11, 16, 22, 32, etc.

What are appropriate exposure parameters used to find?
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A: unanswerable


Problem: Hanover:

In September 1941, through the "Action Lauterbacher" plan, a ghettoisation of the remaining Hanoverian Jewish families began. Even before the Wannsee Conference, on 15 December 1941, the first Jews from Hanover were deported to Riga. A total of 2,400 people were deported, and very few survived. During the war seven concentration camps were constructed in Hanover, in which many Jews were confined. Of the approximately 4,800 Jews who had lived in Hannover in 1938, fewer than 100 were still in the city when troops of the United States Army arrived on 10 April 1945 to occupy Hanover at the end of the war.[citation needed] Today, a memorial at the Opera Square is a reminder of the persecution of the Jews in Hanover. After the war a large group of Orthodox Jewish survivors of the nearby Bergen-Belsen concentration camp settled in Hanover.

When did the Russian army arrive to occupy Hanover?
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A: unanswerable


Problem: Elevator:

To prevent this problem, in one implementation of destination control, every user gets an RFID card to identify himself, so the system knows every user call and can cancel the first call if the passenger decides to travel to another destination to prevent empty calls. The newest invention knows even where people are located and how many on which floor because of their identification, either for the purposes of evacuating the building or for security reasons. Another way to prevent this issue is to treat everyone travelling from one floor to another as one group and to allocate only one car for that group.

What is one way to implement destination control?
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A: every user gets an RFID card to identify himself


Problem: Glacier:

Glaciers are broken into zones based on surface snowpack and melt conditions. The ablation zone is the region where there is a net loss in glacier mass. The equilibrium line separates the ablation zone and the accumulation zone; it is the altitude where the amount of new snow gained by accumulation is equal to the amount of ice lost through ablation. The upper part of a glacier, where accumulation exceeds ablation, is called the accumulation zone. In general, the accumulation zone accounts for 60–70% of the glacier's surface area, more if the glacier calves icebergs. Ice in the accumulation zone is deep enough to exert a downward force that erodes underlying rock. After a glacier melts, it often leaves behind a bowl- or amphitheater-shaped depression that ranges in size from large basins like the Great Lakes to smaller mountain depressions known as cirques.

What is based on suface ice and melt conditions?
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A:
unanswerable