B. Sound, because everything else sits still and sound waves move
Answer:
huh? do you need help on math?
Explanation:
what do you mean?
Answer:
As the "plates" on each side of ridges in the seafloor are pulled away, lava comes up from the middle, hardens and "records" the current magnetic field.
Explanation:
I'd guess at valve B. more information about the interesting question would help.
To reduce friction between two surfaces, you have to
make the surfaces smoother.
The best way to do that is to introduce a fluid between them,
like grease, oil, or air.
