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

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

单项选择题A chart projection depicting the poles and a small area on either side of a connecting meridian，that is sometimes used for star charts，is the（）.

A.azimuthal gnomonic projection
B.Lambert conformal projection
C.transverse Mercator projection
D.polyconic projection

单项选择题A chart position enclosed by a square is a(n)（）.

A.fix
B.estimated position
C.dead reckoning position
D.running fix

单项选择题A change of a documented vessel’s name can only be made by the（）.

A.American Bureau of Shipping
B.Commissioner of Customs
C.Treasury Department
D.Coast Guard

单项选择题A chain bridle is used when towing astern because it（）.

A.is easy to connect
B.provides an effective catenary and absorbs shock due to its weight
C.makes rigging a swivel unnecessary
D.prevents the tow from yawing by the drag of the chains in a seaway