Maritime Safety Information()International SafetyNet Service and NAVTEX Service.
A. consists of
B. can be received
C. is transmitted by
D. Are made o
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钢筋混凝土中的钢筋是为了弥补混凝土()的缺陷,这样制成的构件既能受压,又能受拉,从而扩大了混凝土的适用范围。
灯显调车控制空线推进运行时,窗口限速为()。
A. +30km/h
B. +31km/h
C. +33km/h
D. +35km/h