(a) When I did this exercise, I found that the Moon was most precisely covered by 
a small, disk-shaped breath mint.

(b) Using a ruler, I found the breath mint to have a diameter of 0.8 cm, and the 
distance between my eye and my outstretched hand to be 65 cm.  The angle subtended 
is thus given by "x" where

           x             x       0.7 cm
      ------------- = --------  --------
       360/(2*pi)     57.3 deg   65  cm

So x = (0.7 * 57.3 deg) / 65 = 0.62 degree of arc.