单项选择题
A.always move slowly
B.are in one place only
C.sometime move sometime don‟t move
D.are synchronizing with the movement of the earth
单项选择题 What following is not among the functions of SOLAS ships?（）
单项选择题 The existing terrestrial radio system has a number of basic flaws which（）.
单项选择题 When receiving a distress alert, the SAR authorities ashore and the ships in the vicinity of the ship in distress will（）in a coordinated search and rescue operation with the minimum delay.