单项选择题
A.occluded front B.warm front C.cold front D.warm sector
A hygrometer is a device used for determining（）.A.the a...
单项选择题A hygrometer is a device used for determining（）.
A.the absolute temperature B.atmospheric pressure C.wind velocity D.relative humidity
A generally circular low pressure area is called a(n)（）...
单项选择题A generally circular low pressure area is called a(n)（）.
A.cyclone B.anticyclone C.cold front D.occluded front
A frontal thunderstorm is caused by（）.A.pronounced loca...
单项选择题A frontal thunderstorm is caused by（）.
A.pronounced local heating B.wind being pushed up a mountain C.a warm air mass rising over a cold air mass D.an increased lapse rate caused by advection of warm surface air
