This problem shows why the shape of the sun appears to be somewhat flattened at sunset (Fig. 23-57). The sun subtends an angle of approximately 0.5 at the earth. Suppose that a ray from the bottom of the sun's disk is incident on the earth's atmosphere at an angle of 89.0, and a ray from the top of the sun's disk is incident on the atmosphere at an angle of 88.5. Find the angle between the two rays as they strike the earth's surface. Treat the atmosphere as a flat layer with a uniform refractive index of 1.0003. Sun ZanthAnga 2=88-5 0, = 89