单项选择题
In the GMDSS, MSI broadcasts will be made on two dedicated systems:（）and（）.
A.NBDP/VHF radio B.Inmarsat safetyNet/NAVTEX C.Safety service / Inmarsat-A D.Long range / short range
单项选择题 International SafetyNet and Navtex Services promulgate MSI by means of（）.
单项选择题 With the help of modern technology, ships are able to receive automated broadcast of safety messages（）.
单项选择题 When the power of a SART is on , it will（）.
