The problem: Answer a question about this article:
The simplest way to gain information about brain anatomy is by visual inspection, but many more sophisticated techniques have been developed. Brain tissue in its natural state is too soft to work with, but it can be hardened by immersion in alcohol or other fixatives, and then sliced apart for examination of the interior. Visually, the interior of the brain consists of areas of so-called grey matter, with a dark color, separated by areas of white matter, with a lighter color. Further information can be gained by staining slices of brain tissue with a variety of chemicals that bring out areas where specific types of molecules are present in high concentrations. It is also possible to examine the microstructure of brain tissue using a microscope, and to trace the pattern of connections from one brain area to another.
Brain tissue is naturally soft, but can be stiffened with what liquid?
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The answer: alcohol

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Many ground crew at the airport work at the aircraft. A tow tractor pulls the aircraft to one of the airbridges, The ground power unit is plugged in. It keeps the electricity running in the plane when it stands at the terminal. The engines are not working, therefore they do not generate the electricity, as they do in flight. The passengers disembark using the airbridge. Mobile stairs can give the ground crew more access to the aircraft's cabin. There is a cleaning service to clean the aircraft after the aircraft lands. Flight catering provides the food and drinks on flights. A toilet waste truck removes the human waste from the tank which holds the waste from the toilets in the aircraft. A water truck fills the water tanks of the aircraft. A fuel transfer vehicle transfers aviation fuel from fuel tanks underground, to the aircraft tanks. A tractor and its dollies bring in luggage from the terminal to the aircraft. They also carry luggage to the terminal if the aircraft has landed, and is being unloaded. Hi-loaders lift the heavy luggage containers to the gate of the cargo hold. The ground crew push the luggage containers into the hold. If it has landed, they rise, the ground crew push the luggage container on the hi-loader, which carries it down. The luggage container is then pushed on one of the tractors dollies. The conveyor, which is a conveyor belt on a truck, brings in the awkwardly shaped, or late luggage. The airbridge is used again by the new passengers to embark the aircraft. The tow tractor pushes the aircraft away from the terminal to a taxi area. The aircraft should be off of the airport and in the air in 90 minutes. The airport charges the airline for the time the aircraft spends at the airport.
How long should it take for an aircraft to be off the airport and in the air?
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The answer: 90 minutes

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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.
Most crevices are no deeper than what measure?
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The answer: 46 m (150 ft)

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Boston's coastal location on the North Atlantic moderates its temperature, but makes the city very prone to Nor'easter weather systems that can produce much snow and rain. The city averages 43.8 inches (1,110 mm) of precipitation a year, with 43.8 inches (111 cm) of snowfall per season. Snowfall increases dramatically as one goes inland away from the city (especially north and west of the city)away from the moderating influence of the ocean. Most snowfall occurs from December through March, as most years see no measurable snow in April and November, and snow is rare in May and October. There is also high year-to-year variability in snowfall; for instance, the winter of 201112 saw only 9.3 in (23.6 cm) of accumulating snow, but the previous winter, the corresponding figure was 81.0 in (2.06 m).[d]
What is the average snowfall per year in the City of Boston?
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The answer:
43.8 inches