Theloranlinesdrawnonnavigationchartsrepresent().
A. Groundwaves
B. Skywaves
C. Eithergroundwavesorskywavesinterchangeably
D. Anaveragebetweengroundwaveandskywavepositions
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Thereceiveruses()satellitestocomputelatitude,longitude,altitude,andvelocity.
A. one
B. two
C. three
D. four
以下关于如意金黄散的说法错误的是()
A. 用于疮疡初起,红肿热痛
B. 外用药
C. 使用时可用清茶或蜂蜜调敷
D. 外敷面积不宜超出肿胀范围
TheuseofpulsegroupsandextremelyprecisetimingateachLoran-Cstationmakespossibletheuseof().
A. Highfrequencypulses
B. Combinationsofhighandlowfrequencypulses
C. Thesamefrequencyforallstationsinachain
D. Variedlongandshortpulses
ToobtainaccuracyinfixingbyDF,()andthreestationsshouldbeused.
A. Parallelbearings
B. Long-rangebearings
C. Short-rangebearings
D. Crossbearings