(20 14? Due to the existence of the atmosphere on the earth's surface, the sunrise observed by people in the morning will be advanced for a period of time.

The optical path diagram is shown in the figure.

"OO" is the normal state, and ED is the horizon. In normal weather, the incident light is AB, the incident angle is I, the refracted light is BD, and the refraction angle is R. In foggy weather, the incident light is CB, the incident angle is I', the refracted light is BD, and the refraction angle is still R. The included angle between AB and CB is α.

Yes: sinisinr=n 1①

Sini’SINR = N2②

sinr=RR+h③

α= I′-I？ ④

The joint solution is α = sin-1n2r+h-sin-1n1RR+h.

Answer: The included angle α between the sun's incident light at sunrise in normal weather and the sun's incident light at sunrise in foggy morning is sin-1n2r+h-sin-1RR+h. 。