单项选择题
A.the vessel has enough room to swing while at anchor
B.the anchor flukes bite into the ocean bottom
C.there is a sufficient scope of chain to keep the anchor on the bottom
D.there is more chain out than there is in the chain locker
单项选择题 A strong，often violent，northerly wind occurring on the Pacific coast of Mexico，particularly during the colder months，is called（）.
单项选择题 A stretch where the channel changes from one side of the river to the other is called a （）.
单项选择题 A storm’s track is characterized by all of the following except（）.