When the word “radar” is used alone, it usually includes _______ .
A.both primary and secondary radar
B.both PAR and SSR
C.primary radar only
D.secondary radar only
正确答案是A
When the word “radar” is used alone, it usually includes _______ .
A.both primary and secondary radar
B.both PAR and SSR
C.primary radar only
D.secondary radar only
正确答案是A