单项选择题
A.Upwind B.Downwind C.Crosswind D.Downcurrent
Early indications of the approach of a hurricane may be...
单项选择题Early indications of the approach of a hurricane may be all of the following EXCEPT（）.
A.short confused swells B.gradually increasing white clouds (mare's tails) C.pumping barometer D.continuous fine mist-like rain
Cirrus clouds are composed primarily of（）.A.ice crystal...
单项选择题Cirrus clouds are composed primarily of（）.
A.ice crystals B.water droplets C.snow crystals D.nitrogen
An aneroid barometer reading should be corrected for di...
单项选择题An aneroid barometer reading should be corrected for differences in（）.
A.elevation B.temperature C.wind speed D.latitude
