Answer:
3. [tex]h^2[/tex]
Explanation:
Energy of volume contained in a dam is given by
[tex]E=\dfrac{1}{2}A\rho gh^2[/tex]
where,
A = Horizontal surface area of the barrage
[tex]\rho[/tex] = Density of water
g = Acceleration due to gravity = 9.81 m/s²
h = Vertical tidal range,
It can be seen that
[tex]E\propto h^2[/tex]
Hence, the energy is proportional to [tex]h^2[/tex]