A sylphon cell is a part of a（）.

单项选择题A sea breeze is a wind（）.

A.that blows towards the sea at night
B.that blows towards an island during the day
C.caused by cold air descending a coastal incline
D.caused by the distant approach of a hurricane

单项选择题A millibar is a unit of（）.

A.humidity
B.precipitation
C.pressure
D.temperature

单项选择题A microbarograph is a precision instrument that provides a（）.

A.charted record of atmospheric temperature over time
B.charted record of atmospheric pressure over time
C.graphic record of combustible gases measured in an atmosphere
D.graphic record of vapor pressure from a flammable/combustible liquid

单项选择题A mercurial barometer at sea is subject to rapid variations in height (pumping) due to the pitch and roll of the vessel. To avoid this error，measurements of atmospheric pressure at sea are usually measured with a(n)（）.

A.syphon barometer
B.cistern barometer
C.aneroid barometer
D.fortin barometer

单项选择题A low，uniform layer of cloud resembling fog，but not resting on the ground，is called（）.

A.cumulus
B.nimbus
C.stratus
D.cirrus