97免费在线观看视频,亚洲综合自拍网,黄色毛片免费观看,热久久综合网,免费看日产一区二区三区 狠狠操av,久久久涩涩涩,在线精品免费视频,人人插天天干,久久91精品国产91久久

單項選擇題

1 nautical mile is the lenth of an arc of a great circle which subtends an angel of()at the center of the Earth.

A.1degree
B.1 minute
C.1second
D.1.5 degree

微信掃碼免費搜題