单项选择题
In ship construction，frame spacing is（）.
A.greater at the bow and stern B.reduced at the bow and stern C.uniform over the length of the vessel D.uniform over the length of the vessel，with the exception of the machinery spaces，where it is reduced due to increased stresses
单项选择题 In relation to cargo gear，what does SWL mean?（）.
单项选择题 In nautical terminology a dog is a（）.
单项选择题 If the engine of a survival craft does not start，check to see（）.
