[填空题]
Eclipses happen on Eal; dn 9s3lq9grrth becausp2ol1i q i-ujfi7v;7 b/kf:dip g+8iwe of an amazing coincidence. Calculate, using the information inside the Front Cover, the angular diameters (in rd/f jvo:l+w8i1b i f2i7g ip-kpq;7uiadians) of the Sun and the Moon, as seen on Earth. Sun = $rad$ Moon = $rad$