A tropical storm is building strength some distance from your ship. Waves are coming from the east，with periods increasing from 5 seconds to 15 seconds. The swell is from the east. Where was the storm when these new swells were generated? （）

单项选择题A tropical cyclone has recurved and entered temperate latitudes. In the Northern Hemisphere when a large high pressure system lies north of the storm，what situation may occur?（）

A.The low may suddenly deepen，and the cyclone intensify and pick up speed
B.The left semicircle may become the dangerous semicircle
C.The low and the high may merge and cancel out the weather characteristics of each
D.The high may force the cyclone to reverse its track

单项选择题A sylphon cell is a part of a（）.

A.maximum thermometer
B.barograph
C.thermograph
D.hygrometer

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