The most doubtful and unpredictable factor in a mooring system is the（）.

单项选择题The lockmaster has given you permission to tie off on the lower guide wall to wait your turn to lock through. What should you be most concerned with? （）

A.A downbound vessel
B.An upbound vessel
C.Current reaction when the lock chamber is being emptied
D.Current reaction when the lock chamber is being filled

单项选择题The length of chain between the anchor and the end of the pendant line is called the（）.

A.pigtail chain
B.thrash chain
C.crown chain
D.wear chain

单项选择题The holding power of an anchor at a given scope of cable increases when the（）.

A.amount of chain lying along the bottom increases
B.length of the catenary is reduced
C.mooring line tension is increased
D.amount of chain lying along the bottom decreases

单项选择题The holding capabilities of an anchor are determined PRIMARILY by the（）.

A.design of the anchor
B.weight of the anchor
C.scope of the anchor chain
D.size of the vessel

单项选择题The best method of determining if a vessel is dragging anchor is to note（）.

A.the amount of line paid out
B.how much the vessel sheers while at anchor
C.any change in the tautness of the anchor chain
D.changes in bearings of fixed objects onshore