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（）.
A.Tehuan tepecer B.Papagayo C.Norther D.Pampero
单项选择题 A storm is forecast for the area where your vessel is moored. For its safety you should put（）.
单项选择题 A steep barometric gradient indicates（）.
单项选择题 A katabatic wind blows（）.
