Two retro "Quality" badges.
The one on left was interesting in terms of fractions (sectors) of circles being used. Rather than try to build the bottom black shape by uniting one circle with a huge circle following that radius, I drew the smaller circle and used the pen tool to draw a line, add a mid point and set it as a curved anchor, then placed the mid point onto the desired radius. Shape builder was used to remove the larger sector which I no longer needed. Banner was made using the arc effect at 20% (same device used for banner text). The balls were done by creating the top one, the with the Rotate tool (ALT clicking to set the ball's rotational centre as the main circle's centre) and repeating the move with Cntrl D one way, then working from the top with the same value but negative.
Second design made use of applying a zig zag effect to a circular path. The "corn motif" is two ellipses angled 45 degrees from the horizontal, then rotated as the ball motif in above example (remember ALT Click to set the central point where the element rotates around. The first move is previewed (360 degrees/160 ) was decided upon (160 elements in the rotation), then repeated Cntrl D until coming full circle, so to speak! I shall need to read up on applying text to a circular path.