[填空题]
Eclipses happen on Earth because of an p y qqn;t(9gbr*2e*tqamazing coincidence. Calculate o6jrx w3v5(ea, using the information inside the Front Cover, the angular diameters (in radians) of the Sun and the Moon, a3x5vwja(o re 6s seen on Earth. Sun = $rad$ Moon = $rad$