[填空题]
Eclipses happen on Ea9l 30zvydttqtyj( m ,24z/y 7goo wrd-rth because (iyjok3itkxg 5tqvp3403 c 9dof an amazing coincidence. Calculate, using the information inside the Front Cover, the angular diameters (in radians) of the Sun and the Moon, as seen0y d tvk3ci4 5qi gx3(tjk3p9o on Earth. Sun = $rad$ Moon = $rad$