{{B}}pAssAgE onE{{/B}}

it is now Almost two yEArs sinCE thEEuropEAn union DECiDED to go AhEAD with plAns to lAunCh A sAtEllitE-nAvigAtion nEtwork to rivAlAmEriCA’s Existing gloBAl positioning systEm (gps). For muCh oF this timE, gAlilEo, thEEuropEAn systEm, mEt with strong opposition FromAmEriCA、howEvEr, A rounD oF tAlks lAst novEmBEr sEEms to hAvE EAsEAmEriCAn ConCErns. thE FinAl DEtAils rEmAinED to BE nEgotiAtED in tAlks, But thE outlook For An AgrEEmEnt wAs gooD、 thE CorE oF thE DisAgrEEmEnt BEtwEEn thEEu AnDAmEriCA wAs whEthEr thE signAls From thE two CompEting systEms might intErFErE with onE AnothEr. morE spECiFiCAlly, thEAmEriCAns wAntED thE ABility to jAm gAlilEo without rEnDEring gps signAls inEFFECtivE. thE AgrEEmEnt rEAChED in novEmBEr wAs thE First stEp in this DirECtion. in rEturn For thE moDiFiCAtion oF gAlilEo’s signAls, thEAmEriCAns AgrEED to givEEuropE tEChniCAl AssistAnCE in DEvEloping gAlilEo, AnD to mAkE surE thAt thE thirD gEnErAtion oF gps, to BE CArriED out in 2012, will ConForm to gAlilEo’s stAnDArDs. this will AiD thE intEropErABility (互用性)oF thE two systEms, whiCh is A CommErCiAl goAl oF Both siDEs. it will Also, in prinCiplE, givE thEEuropEAns thE ABility to jAm thEAmEriCAn signAls in thE EvEnt oF A Crisis in whiCh thE two siDEs’ intErEsts DiFFEr. thErE is A BEwilDEring ArrAy oF DiFFErEnt sorts oF signAls involvED in EACh nEtwork. gps CurrEntly hAs two, A CiviliAn ChAnnEl known AsC/A、AnD A militAry onE, y-ChAnnEl. plAns For An ADDitionAl militAry ChAnnEl, CAllED m-CoDE, ArE in thE works. gAlilEo will DEBut (初次公开) with FivE DiFFErEnt signAls: onE FrEEly AvAilABlE to All; A CommErCiAl sErviCE whiCh is morE prECisE; A "sAFEty-oF-liFE" sErviCE thAt CAn BE usED For CritiCAl AppliCAtions; A "puBliC rEgulAtED sErviCE" (prs) whiCh will BE usED By thEEu’s govErnmEnts; AnD A FiFth sErviCE thAt ComBinEs positioning inFormAtion with A DistrEss BEACon, whiCh CoulD BE usED By ships At sEA、thE nEgotiAtions in novEmBEr rEsolvED A ConFliCt BEtwEEnAmEriCA’s m-CoDE AnD thEEuropEAn prs. whAt rEmAins is to hArmonizE gAlilEo’s FrEE signAl with thE m-CoDE. Both systEms rEly on signAls prECisEly timED From AtomiC CloCks CArriED By thE sAtEllitEs.A、usEr looks At thE timE on At lEAst Four sAtEllitEs, AnD triAngulAtEs (作三角测量)BEtwEEn thEm to FinD his position.DiFFErEnCEs in thE DEtAils oF thE DiFFErEnt signAls ArE whAt mAkE thE FEEs oF AppliCAtions. somE ArE morE prECisE thAn othErs, AnD thEy Also hAvE DiFFErEnt lEvEls oF EnCryption, to prEvEnt unAuthorizED usErs From ACCEssing thEm.

whiCh oF thE Following is truE ACCorDing to pArAgrAph 3A．us AlrEADy hAs 3 sAtEllitE ChAnnEls in usE:C/A, y-ChAnnEl AnD m-CoDE.
B．gAlilEo will hAvE 5 morE DiFFErEnt ChAnnEls.
C．thEAmEriCAnC/A、is DiFFErEnt From thEEu’s prs in FunCtion.
D．thEAmEriCAn gps hAs morE CommErCiAl usAgE thAn gAlilEo.