A.complicated circumstances
B.changeable atmospheric pressure
C.large density of traffic
D.some strong signals from unwanted satellites
您可能感興趣的試卷
你可能感興趣的試題
A.besides the polar regions
B.including the North Pole and the South Pole
C.above 70N and below 70S
D.as far north and south 70
A.Space segment, NCC, RCC, SES and CES
B.Space Segment, a satellite system, C system, NCC and NCS
C.Space Segment, NCC, NCS,CES and SES
D.A system, C system, satellite system, earth stations and NCS
A.4
B.9
C.8
D.5
A.the weather over there is always terrible
B.the condition there is complicated
C.the signals are too strong
D.their SES may receive the signals from unwanted satellite
A.sometimes
B.all times
C.never
D.partly
最新試題
Radio communication（）for many years and helps to save tens of thousands of lives.
At least two two-way VHF radiotelephone apparatus shall be provided on every cargo ship of（）tons gross tonnage and upwards but less than 500 tons gross tonnage.
Please use（）for（）.
International Navtex service means the coordinated broadcast and automatic reception on（）khz of maritime safety information by narrow-band direct-printing telegraphy using English language.
Can MF/HF radiotelephone receive the MSI sent from the coast stations alone?（）
All coast radio stations（）DSC installed for VHF and HF.
Ship-to-ship distress alerting should be conducted by（）.
By using（）system a ship can send a distress message and know with certainty it will be received.
On-scene communications will normally take place between（）.
COSPAS-SARSAT is intended to be used for（）.