[填空题]
Eclipses happen on Earip.qda 3 e4ykhsu+,2cffz0/l th j8b /chgz 3r s1+*lhjdeb+wdso8+a+ obecause of an amazing coincidence. Calculate, using the information inside the Front Cover, the angular diameters (in radians) of the Sun and the Moon, as seen on Earjgo8 ds leha+*obsj/3+1h rwc+bd8 +zth. Sun = $rad$ Moon = $rad$