单项选择题 On the pole side of the high pressure belt in each hemisphere，the pressure diminishes. The winds along these gradients are diverted by the Earth’s rotation toward the east and are known as the（）.

单项选择题 On a working copy of a weather map，a cold front is represented by what color line? （）

单项选择题 Navigational warnings and weather bulletins for shipping（）from Singapore Radio.