Following observations are taken from a travelling microscope to determine the refractive index of a liquid. Reading for the bottom of an empty beaker = $12.324\,\text{cm}$. Reading for the bottom of the beaker when partially filled with the liquid = $12.802\,\text{cm}$. Reading for the liquid surface = $13.895\,\text{cm}$. What is the refractive index of the liquid?