The answer is seafloor spreading
X would equal 5. (need more characters)
Channel Tunnel, CN Tower, Empire State Building, Golden Gate Bridge, Itaipu Dam, North Sea Protection Works (Netherlands), Panama Canal. Hope this helps!
I believe the answer is False
Answer: D
Explanation: Newton’s Law. The more mass two objects have, the greater the force of gravity the masses exert on each other. If one of the masses is doubled, the force of gravity between the objects is doubled.