单项选择题
A.moderate but easily navigated
B.calm
C.mountainous and confused
D.mountainous but fairly regular as far as direction is concerned
单项选择题 In the Northern Hemisphere，when the wind at your location is northerly，the low pressure center causing the wind is located to your（）.
单项选择题 In the Northern Hemisphere，the right half of the storm is known as the dangerous semicircle because（）.
单项选择题 In the Northern Hemisphere，if your vessel is in a hurricane’s navigable semicircle it should be positioned with the wind on the（）.