单项选择题
The required number and type of hand portable fire extinguishers for staterooms on cargo vessels is（）.
A.one A-I B.one B-I C.one C-I D.none required
单项选择题 The purpose of inert gas systems aboard tank vessels is to（）.
单项选择题 The primary objective of a Ro-Ro vessel is to（）.
单项选择题 The piping that routes an oil cargo from the manifold to underdeck pipelines is known as a （）.
