单项选择题
The portable radio apparatus means（）.
A.the radio apparatus fitted on the portside B.the radio with a portable equipment C.the radio equipment which is easily movable D.the portable radio with some apparatus
单项选择题 The most common type of davit found on merchant vessels today is the（）.
单项选择题 The holding capability of an anchor is primarily determined by the（）.
单项选择题 The function of the bypass valve on the self-contained breathing apparatus is to（）.
