单项选择题
A.DR plot B.track line C.heading D.estimated course
The only cylindrical chart projection widely used for n...
单项选择题The only cylindrical chart projection widely used for navigation is the （）.
A.Lambert conformal B.Mercator C.azimuthal D.gnomonic
The numeral in the center of a wind rose circle on a pi...
单项选择题The numeral in the center of a wind rose circle on a pilot chart indicates the （）.
A.total number of observations B.average wind force on the Beaufort scale C.average wind force in knots D.percentage of calms
The maximum difference between mean time and apparent t...
单项选择题The maximum difference between mean time and apparent time is （）.
A.equal to the longitude expressed in time units B.about 16 minutes C.the difference between the GHA of mean sun and the first point of Aries D.15°of arc
