A.moderate but easily navigated B.calm C.mountainous and confused D.mountainous but fairly regular as far as direction is concerned
单项选择题In the doldrums you will NOT have().
A.high relative humidity B.frequent showers and thunderstorms C.steep pressure gradients D.frequent calms
单项选择题In the doldrums you can expect().
A.steady,constant winds B.frequent rain showers and thunderstorms C.steep pressure gradients D.low relative humidity
单项选择题In reading a weather map,closely spaced pressure gradient lines would indicate().
A.high winds B.high overcast clouds C.calm or light winds D.fog or steady rain
单项选择题In North America the majority of the weather systems move from().
A.north to south B.south to north C.east to west D.west to east
单项选择题In bad weather,what length of chain should be used with a single anchor? ()
A.3 times the depth of water B.6 times the depth of water C.10 times the depth of water D.15 times the depth of water