It can be inferred from the passage that by the end of World War II, most Americans ___

A Doppler speed log indicates speed over ground ______.

A.at all times

B.in the bottom return mode

C.in the volume reverberation mode

D.only when there is no current

A Doppler log in the volume reverberation mode indicates the ______.

A.speed being made good

B.speed through the water

C.the set of the current

D.the depth of the water

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

The speed of sound through ocean water is nearly always ().

A.Faster than the speed of calibration for the fathometer

B.The same speed as the speed of calibration for the fathometer

C.Slower than the speed of calibration for the fathometer

D.Faster than the speed of calibration for the fathometer，unless the water is very warm

Which of the following will affect the voice quality through Internet？

A．The speed of your voice.

B．The speed of the Internet.

C．The Internet traffic.

D．The service of the operator.

Which of the following will affect the voice quality through Internet？

A．The speed of your voice.

B．The speed of the Internet.

C．The Internet traffic.

D．The service of the operator.

Which of the following will affect the voice quality through Internet？

A．The speed of your voice.

B．The Internet traffic.

C．The speed of the Internet.

D．The service of the operator.

A．Table

B．Index

C．View

D．Log