单项选择题
Risk of collision exists when an approaching vessel has a(n)（）.
A.generally steady bearing and decreasing range B.generally steady range and increasing bearing C.increasing range and bearing D.decreasing bearing only
单项选择题 On a gnomonic chart，a great circle track between Los Angeles and Brisbane will appear as a （）.
单项选择题 Mariners proceeding across the main routes are recommended to do so at（）.
单项选择题 Mariners proceeding across the main routes are（）to do so at as wide an angle as practicable.
