单项选择题
A.make command of
B.take command of
C.get command of
D.have command of
单项选择题 A group of crew members standing by in case of an emergency in order to assist other teams in action if necessary is a（）.
单项选择题 A pattern according to which vessels and / or aircraft may conduct a co-ordinated search is a（）.
单项选择题 A VESSEL，OTHER THAN A RESCUE UNIT，DESIGNATED TO CO-ORDINATE SURFACE SEARCH AND RESCUE OPERATION WITHIN A SPECIFIED AREA is known as（）.