单选题As a ship moves through the water，it drags with it a body of water called the wake. The ratio of the wake speed to the ship’s speed is called（）.Apropeller velocityBspeed of advanceCwake distributionDwake fraction
单选题
As a ship moves through the water，it drags with it a body of water called the wake. The ratio of the wake speed to the ship’s speed is called（）.
A
propeller velocity
B
speed of advance
C
wake distribution
D
wake fraction
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