从事非拖网作业的船舶在航不对水移动在雾中应鸣放的声号是:() ["一长声","两长声","一长两短","五短声"]
以下方法中属于定性差异比较法的有()。 ["比例法","简单对比法","多项比较法","评分法"]
锚泊中从事清除水雷作业的船舶在雾中应鸣放的声号是:() ["一长声","两长声","一长两短","五短声"]
品评培训的最佳时间为()。 ["春秋季","上午7~8点","下午3~5点","晚上"]
雾航中,听到一长两短声号,该船可能是:() Ⅰ、失去控制的船舶Ⅱ、从事捕鱼船Ⅲ、操纵能力受到限制的船舶 ["Ⅰ","Ⅰ、Ⅱ","Ⅱ、Ⅲ","Ⅰ、Ⅱ、Ⅲ"]
竞技体育的概念是什么?