Q: What is a question about this article? If the question is unanswerable, say "unanswerable".
Larger SAMs may be deployed in fixed launchers, but can be towed/re-deployed at will. The SAMs launched by individuals are known in the United States as the Man-Portable Air Defence Systems (MANPADS). MANPADS of the former Soviet Union have been exported around the World, and can be found in use by many armed forces. Targets for non-ManPAD SAMs will usually be acquired by air-search radar, then tracked before/while a SAM is "locked-on" and then fired. Potential targets, if they are military aircraft, will be identified as friend or foe before being engaged. The developments in the latest and relatively cheap short-range missiles have begun to replace autocannons in this role.
What are the SAMs called that are launched by individuals in the US?
A: MANPADS

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The army is also changing its base unit from divisions to brigades. Division lineage will be retained, but the divisional headquarters will be able to command any brigade, not just brigades that carry their divisional lineage. The central part of this plan is that each brigade will be modular, i.e., all brigades of the same type will be exactly the same, and thus any brigade can be commanded by any division. As specified before the 2013 end-strength re-definitions, the three major types of ground combat brigades are:
Who can command any brigade?
A: divisional headquarters

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Extending across the north and south side of the Alps in west-central Europe, Switzerland encompasses a great diversity of landscapes and climates on a limited area of 41,285 square kilometres (15,940 sq mi). The population is about 8 million, resulting in an average population density of around 195 people per square kilometre (500/sq mi). The more mountainous southern half of the country is far more sparsely populated than the northern half. In the largest Canton of Graubünden, lying entirely in the Alps, population density falls to 27 /km² (70 /sq mi).
What is the average population density of Switzerland?
A: 195 people per square kilometre (500/sq mi)

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According to the International Energy Agency, cellulosic ethanol biorefineries could allow biofuels to play a much bigger role in the future than organizations such as the IEA previously thought. Cellulosic ethanol can be made from plant matter composed primarily of inedible cellulose fibers that form the stems and branches of most plants. Crop residues (such as corn stalks, wheat straw and rice straw), wood waste, and municipal solid waste are potential sources of cellulosic biomass. Dedicated energy crops, such as switchgrass, are also promising cellulose sources that can be sustainably produced in many regions.
What are potential sources of cellulosic biomass?
A:
Crop residues