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【单选题】
INMARSAT第二代卫星中1626.5—17.5MHZ是（）的通信频带
A.
船到星
B.
星到船
C.
岸到星
D.
星到岸
参考答案：
参考解析：
刷刷题刷刷变学霸
举一反三
【单选题】第二篇 Sleep We all know that the normal human daily cycle of activity is of some 7 - 8 hours’ sleep alternating with some 16 - 17 hours’ wakefulness and that, broadly speaking, the sleep n...
A.
people hate the inconvenience of working on night shifts.
B.
your life is disturbed by changing from day to night routines and back.
C.
not all industries work at the same hours.
D.
it is difficult to find a corps of good night workers.
【单选题】第二篇 A Fire near Waco Six years later, in an about-face, the Federal Bureau of Investigation(FBI) admits that federal agents fired tear gas canisters capable of causing a fire at the Bran...
A.
neutral
B.
bitter
C.
excited
D.
expectant
【单选题】在多进制调制系统中，当Rb相同时，增加进制数M，或RB相同时，增加进制数M，对频带利用率ηb的影响分别是（）。
A.
提高，提高
B.
减小，减小
C.
提高，减小
D.
减小，提高