单项选择题 In mid-ocean，the characteristics of a wave are determined by three factors. What is NOT one of these factors?（）.

单项选择题 In a tropical cyclone，in the Northern Hemisphere，a vessel hove to with the wind shifting counterclockwise is（）.

单项选择题 Cold water flowing southward through the western part of the Bering Strait between Alaska and Siberia is joined by water circulating counterclockwise in the Bering Sea to form the（）.