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1、UnitedStates
2、Geography
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4、People
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6、Government
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8、Economy
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10、Communications
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12、Transportation
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14、Military
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16、TransnationalIssues
17、Geography[TopofPage]Location:NorthAmerica,borderingboththeNorthAtlanticOceanandtheNorthPacificOcean,betweenCanadaandMexicoGeographiccoordinates:3800N,9700WMaprefere
18、nces:NorthAmericaArea:total:9,629,091sqkmland:9,158,960sqkmwater:470,131sqkmnote:includesonlythe50statesandDistrictofColumbiaArea—comparative:aboutone-halfthesizeofRussia;aboutthree-tenthsthesizeofAfrica;aboutone-halfthesizeofSouthAmerica(orslightlylargerthanBrazil);slightlylargert
19、hanChina;abouttwoandone-halftimesthesizeofWesternEuropeLandboundaries:total:12,248kmbordercountries:Canada8,893km(including2,477kmwithAlaska),Cuba29km(USNavalBaseatGuantanamoBay),Mexico3,326kmnote:GuantanamoNavalBaseisleasedbytheUSandthusremainspartofCubaCoastline:19,924kmMaritimec
20、laims:contiguouszone:12nmcontinentalshelf:notspecifiedexclusiveeconomiczone:200nmterritorialsea:12nmClimate:mostlytemperate,buttropicalinHawaiiandFloridaandarcticinAlaska,semiaridinthegreatplainswestoftheMississippiRiverandaridintheGreatBasinofthesouthwest;lowwintertemperaturesinth
21、enorthwestareamelioratedoccasionallyinJanuaryandFebruarybywarmchinookwindsfromtheeasternslopesoftheRockyMountainsTerrain:vastcentralplain,mountainsinwest,hillsandlowmountainsineast;ruggedmountainsandbroadrivervalleysinAlaska;rugged,volcanictopographyinHawaiiElevationextremes:lowest
22、point:DeathValley-86mhighestpoint:MountMcKinley6,194mNaturalresources:coal,copper,lead,molybdenum,phosphates,uranium,bauxite,gold,iron,mercury,nickel,potash,silver,tungsten,zinc,petroleum,naturalgas,timberLanduse:arableland:19%permanentcrops:0%permanentpastures:25%forestsandwoodlan
23、d:30%other:26%(1993est.)Irrigatedland:207,000sqkm(1993est.)Naturalhazards:tsunamis,volcanoes,andearthquakeactivityaroundPacificBasin;hurricanesalongtheAtlanticcoast;tornadoesinthemidwest;mudslidesinCalifornia;forestfiresinthewest;flooding;permafrostinnorthernAlaskaisamajorimpedimen
24、ttodevelopmentEnvironment—
