[填空题]
Eclipses happen on Earth because of an am*s60y dohxgm 9 ll2,eyazing coincidence. Calculate, using t hm, bx(w)z ilka91b9lhe information inside the Front Cover, the angular diameters (in radians1)(9bl9k, wx b hzamil) of the Sun and the Moon, as seen on Earth. Sun = $rad$ Moon = $rad$