"Cumulative List of Amendments to Admiralty List of Radio Signals is published ____times every year.
A.2
B.4
C.6
D.12"
正确答案是B
"Cumulative List of Amendments to Admiralty List of Radio Signals is published ____times every year.
A.2
B.4
C.6
D.12"
正确答案是B