Answer
$h=230.51m$
Work Step by Step
First we calculated the atmospheric pressures:
$P_{top}=\rho_{Hg}*g*h_{top,Hg}=(13600\frac{kg}{m^3})*(9.81\frac{m}{s^2})*(0.675m)=90055.8Pa$
$P_{bottom}=\rho_{Hg}*g*h_{bottom,Hg}=(13600\frac{kg}{m^3})*(9.81\frac{m}{s^2})*(0.695m)=92724.12Pa$
Then the difference of atmospheric pressures is:
$\Delta P=92724.12Pa-90055.8Pa=2668.32Pa$
Knowing that:
$P=\rho*g*h$
$h=\frac{P}{\rho*g}=\frac{2668.32kPa}{1.18\frac{kg}{m^3}*9.81\frac{m}{s^2}}=230.51m$
