单项选择题
A Doppler log in the bottom return mode indicates the（）.
A.velocity of the current B.bottom characteristics C.depth of the water D.speed over the ground
单项选择题 A Doppler log in the volume reverberation mode indicates（）.
单项选择题 A Doppler speed log indicates speed over ground（）.
单项选择题 A double male coupling is one that（）.
