When the rectangular metal tank in the figure is filled to the top with an unknown liquid, observer O, with eyes level with the top of the tank, can just see corner E. A ray that refracts toward O at the top surface of the liquid is shown. In terms of D and L, what is the index of refraction of the liquid? Normal to liquid surface nliquid =

When the rectangular metal tank in the figure is filled to the top with an unknown liquid, observer O, with eyes level with the top of the tank, can just see corner E. A ray that refracts toward O at the top surface of the liquid is shown. In terms of D and L, what is the index of refraction of the liquid? Normal to liquid surface nliquid =