Answer:

Explanation:
From the equation we are told that:
Velocity of French sub 
Velocity of U.S. sub at 
French Wave Frequency 
Velocity of wave 
Generally the equation for Signal's frequency as detected by the U.S. is mathematically given by
Doppler effect



Reserves might last 53.3 years.
Earth’s mineral resources:
Answer:
the answer here would be A
Answer:
I would disagree with my friend because that according to Newton's first law, an object in motion will continue to be in motion until stopped by another object/force. If the object is already moving, it will stay in motion until something else stops it. There is no need for a force to be <em>continually</em> applied to it while it's already moving.