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

0f the following, the most important consideration for a tank vessel is().

A.GM
B.the vertical center of gravity
C.the longitudinal center of gravity
D.the stress on the hull

微信掃碼免費搜題