[填空题]
Eclipses happen on Earth because of an amazingu vixa-3o:wmf2w*jf 3 coincidence. Calculate, usrh 6jt+h.s*sding the information inside the Front Cover, the angular diameters (in radians) 6htd sjh*r.+s of the Sun and the Moon, as seen on Earth. Sun = $rad$ Moon = $rad$