心源性呼吸困难的主要原因是:

A、肺循环瘀血
B、体循环瘀血
C、气道痉挛狭窄
D、呼吸中枢兴奋
E、极度紧张、恐慌
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正确答案:

A

答案解析:

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WhatisBillgoingtodo?

A、reserveameetingroom
B、orderrefreshment
C、findacomputer

Intheearlieststagesofman'sdevelopmenthehadnomoreneedofmoneythananimalshave.Hewascontentwithverysimpleformsofshelter,madehisownroughtoolsandweaponsandcouldprovidefoodandclothingforhimselfandhisfamilyfromnaturalmaterialsaroundhim.Ashebecamemorecivilized,however,hebegantowantbettershelter,moreefficienttoolsandweapons,andmorecomfortableandmorelastingclothingthancouldbeprovidedbyhisownneighborhoodorbytheworkofhisownunskilledhands.Forthesethingshehadtoturntotheskilledpeoplesuchassmiths,leatherworkersorcarpenters.Itwasthenthatthequestionofpaymentarose.

Atfirsthegotwhathewantedbyasimpleprocessofexchange.Thesmithwhohadnotthetimetolookafterlandorcattlewasgladtotakemeatorgrainfromthefarmerinexchangeforanaxeoraplough.Butasmoreandmoregoodswhichhadnofixedexchangevaluecameonthemarket,exchangebecametoocomplicatedtobesatisfactory.Anotherproblemarosewhenthosewhomadethingswantedtogetstocksofwoodorleather,oriron,buthadnothingtoofferinexchangeuntiltheirfinishedgoodswereready.Thusthedifficultiesofexchangeledbydegreestotheinventionofmoney.Insomecountrieseasilyhandledthingslikeseedsorshellsweregivenacertainvalueandthefarmer,insteadofpayingthesmithforanewaxebygivinghimsomemeatorgrain,gavehimsomanyshells.Ifthesmithhadanyshellsleftwhenhehadboughthisfood,hecouldgetstocksoftherawmaterialsofhistrade.Insomecountriesquitelargethingssuchascowsorcamelsorevenbigflatstoneswereusedfortrade.Later,piecesofmetal,bearingvaluesaccordingtotherarityofthemetalandthesizeofthepieces,orcoinswereused.Moneyasweknowithadarrived.

1.Exchangeofgoodsbecamedifficultbecause_________.

Amanbecamemorecivilized

Bsmithsbegantolookafterlandorcattleintheirsparetime

Cmoreandmoregoodswhichhadnofixedexchangealuescametothemarker

Dfarmershadn'tenoughgrainormeattoprovidefor

skilledworkers

2.Moneywasnotuseduntil_______.

Apaperwasinvented

Bpeoplepracticedasimpleprocessofexchange

CnothingcouldbeofferedinexchangeDtheexchangeofonethingforanotherbecametoocomplicated

3.Thebesttitleforthispassageis_____.

AWhatismoney

BWhataremoney'sfunctions.

CTheimportanceofmoney

DThebeginningofmoney

It____alsocreatemorefocusedteamsandlesswastedtime.

A、is
B、was
C、will

Doyouthinkcompaniesshouldprovidesportsfacilitiesfortheirstaff?(Why?)

Besusceptibleto

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