单项选择题
A.64.5E B.178E C.15.5W D.54W
Geostationary satellite are artificial satellite which（...
单项选择题Geostationary satellite are artificial satellite which（）.
A.always move slowly B.are in one place only C.sometimes move and sometime don‟t D.synchronize with the movement of the earth
A radio link between a transmitting earth station and a...
单项选择题A radio link between a transmitting earth station and a receiving earth station through one satellite is named a（）.
A.Radio link B.Space segment C.Satellite link D.upper link
International Navtex service is（）.A.a terrestrial MF sy...
单项选择题International Navtex service is（）.
A.a terrestrial MF system B.a satellite communication system C.a land HF radio system D.a coastal VHF system
