Precisely around 1,800 miles below.
Newton's Third Law- For every action there is an equal and opposite reaction... Does this answer your question? If not, I can explain further...
Answer:
3. 
Explanation:
Energy of volume contained in a dam is given by

where,
A = Horizontal surface area of the barrage
= Density of water
g = Acceleration due to gravity = 9.81 m/s²
h = Vertical tidal range,
It can be seen that

Hence, the energy is proportional to 