A tank that is vented to the atmosphere contains a liquid with a density of $0.9 \mathrm{~g} / \mathrm{cm}^{3}$. A dip tube inserted into the top of the tank extends to a point $1 \mathrm{ft}$ from the bottom of the tank. Air is bubbled slowly through the dip tube, and the air pressure in the tube is measured with a mercury $(\mathrm{SG}=13.6)$ manometer. One leg of the manometer is connected to the air line feeding the dip tube, and the other leg is open to the atmosphere. If the manometer reading is $5 \mathrm{in}$., what is the depth of the liquid in the tank?