Consider a common mirage formed by superheated air immediately above a roadway. A truck driver whose eyes are 2.00 $\mathrm{m}$ above the road, where $n=1.000293,$ looks forward. She perceives the illusion of a patch of water ahead on the road. The road appears wet only beyond a point on the road at which her line of sight makes an angle of $1.20^{\circ}$ below the horizontal. Find the index of refraction of the air immediately above the road surface.