A.Opening and closing the throttleB.Rocking the wingsC.……

单项选择题An advantage of using chain lashing on heavy vehicles aboard Ro-Ro vessels is that it（）.

A.has long life
B.is light weight
C.absorbs shock
D.has fine adjustment

单项选择题An advantage of the Christmas Tree towing method is to（）.

A.increase the towing hawser's catenary and provide more spring
B.reduce catenary，allow operation in shallower water，and to release one barge without breaking up the entire tow
C.enable one tug and its crew without any outside assistance to make up or break down the tow
D.provide rapid delivery of logs from the northwestern United States to Hawaiian sawmills

单项选择题An “on-load” release system on a survival craft means the cable can be released（）.

A.only when the load is taken off the cable
B.only when there is a load on the cable
C.only when activated by the controls at the lowering station
D.at any time

单项选择题An “atoll cloud” forming over an island due to heating of the land during the daytime would be which type? （）

A.Cirrus
B.Cumulus
C.Stratus
D.Nimbus

单项选择题An “ABC” dry chemical fire extinguisher would be LEAST effective against a fire in（）.

A.a mattress
B.spilled liquids such as oil or paint
C.high voltage electrical gear
D.a trash can