A continual worsening of the list or trim of any floating ship indicates（）.

单项选择题A conscious victim who has suffered a blow to the head has symptoms that indicate the possibility of concussion. If the patient feels no indication of neck or spine injury，recommended treatment would include（）.

A.turning the victim's head to the side to keep his airway open
B.positioning the victim so the head is lower than the body
C.giving the victim water if he is thirsty，but no food
D.elevating the head and shoulders slightly with a pillow

单项选择题A common class of wire rope used for mooring is the 6x19 class. What does the 6 represent?（）

A.Factor of safety
B.Number of wires per strand
C.Number of strands per wire rope
D.Number of wires in the core

单项选择题A CO2 extinguisher on a ship which has lost 10% of its charge must be（）.

A.used at the earliest opportunity
B.hydro-tested
C.recharged
D.weighed again in one month

单项选择题A chart with a scale of 1:80，000 would fall into the category of a（）.

A.sailing chart
B.general chart
C.coastal chart
D.harbor chart

单项选择题A chart with a natural scale of 1:160，000 is classified as a（）.

A.sailing chart
B.general chart
C.coast chart
D.harbor chart