99色精品-9色在线-99色在线-99色视频国产欧美日产一区二区三区_亚洲精品亚洲人成在线观看_四虎在线精品永久观看_免费一级a一片久久精

單項選擇題

On a ship，when may a work vest be substituted for a required life preserver?（）

A.To replace a damaged life preserver
B.For use during fire drills
C.For use during boat drills
D.At no time

你可能感興趣的試題

單項選擇題

On a ship，watertight doors should be operated（）.

A.during abandon drill
B.during fire drill
C.weekly
D.when the rig is being moved

單項選擇題

On a ship，a fire drill shall be conducted once every（）.

A.week
B.month
C.crew change
D.other week

<dl id="ryic7"></dl>