题型:单项选择题 With respect to automatic identification systems(AIS),which information is required to be broadcast every 1 to 10 seconds().A.Call sign and IMO numberB.Course over ground and MMSIC.MMSI number and call signD.Route Plan and navigational status 查看答案
题型:单项选择题 案例分析题 读某地等高线地形图(单位:m),回答下列小题。野外宿营时一般不能选择①处的主要原因是()A.处于阴坡,光照条件差B.离河流较远,取水不方便C.位于山脊,风力太大D.处于河谷,靠近陡坡,受山洪和山石威胁 查看答案