A.Moon being at its maximum declination
B.Moon crossing the equator
C.Sun and Moon both being near 0°declination
D.Moon being at perigee

A.the density of the water
B.the air temperature
C.the presence of a high pressure area near it
D.underwater soil conditions

A.At the start of spring，when the Sun is nearly over the equator
B.Only when the Sun and Moon are on the same sides of the Earth and are nearly in line
C.When the Sun and Moon are at approximately 90° to each other，as seen from the Earth
D.When the Sun，Moon，and Earth are nearly in line，regardless of alignment order

A.speed of the current at a particular time
B.maximum speed of the current
C.direction from which the current flows
D.direction in which the current flows

A.at a new or full Moon
B.when the Sun，Moon，and Earth are in line
C.at approximately 28-day intervals
D.when the Moon is at quadrature

A.falls／in
B.has been falling／on
C.has fallen／at
D.is falling／in

A.Add one hour to the times listed under the reference stations
B.Subtract one hour from the time differences listed for the subordinate stations
C.Apply no correction as the times in the reference stations are adjusted for daylight savings time
D.Add 15° to the standard meridian when calculating the time difference

A.at apogee
B.new
C.full
D.All of the above

A.temperature and salinity differences in the water
B.wind and density differences in the water
C.water depth and underwater topography
D.rotation of the Earth and continental interference

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