单项选择题
A.SW'ly direction along the NW coast of Africa B.S'ly direction off the East Coast of Australia C.NW'ly direction along the SW coast of Africa D.SW'ly direction along the SE coast of Greenland
Stand of the tide is that time when（）.A.the vertical ri...
单项选择题Stand of the tide is that time when（）.
A.the vertical rise or fall of the tide has stopped B.slack water occurs C.tidal current is at a maximum D.the actual depth of the water equals the charted depth
Spring tides are tides that（）.A.have lows lower than no...
单项选择题Spring tides are tides that（）.
A.have lows lower than normal and highs higher than normal B.have lows higher than normal and highs lower than normal C.are unpredictable D.occur in the spring of the year
River currents tend to（）.A.Pick up speed where the chan...
单项选择题River currents tend to（）.
A.Pick up speed where the channel widens B.Run slower in the center of the channel C.Hug the inside of a bend D.Cause the greatest depth of water to be along the outside of a bend
