[填空题]
Eclipses happen on Ewyf-;*xztptidc(ks4k h 2,* uarth because of 6t2- c ar7fps;mu hi+fan amazing coincidence. Calculate, using the information inside the Front Cover, the angular diameters (in radians) of the Sun and the Moon, as seen on Erufhi-fpt 2m;7+ s ac6arth. Sun = $rad$ Moon = $rad$