A simple U$-$tube that is open at both ends s partially filled with a heavy liquid of density $000k\frac{g}{m^3}.$ A liquid of density $548k\frac{g}{m^3}$ is hen poured into one arm of the tube, forming column $8\mathrm{.}5$ cm in height, as shown.

light liquid $548k\frac{g}{m^3}$

heavy liquid $1000k\frac{g}{m^3}$

What is the difference in the heights of the two liquid surfaces?

Answer in units of cm$.$