20. Intro Quiz

You may use anything from your posn-util.rkt without comment.

1. Write is-box?: posn -> boolean which returns true when the given point is in the illustrated box.

   

2. Write p-circle.

    p-circle: posn(center) posn(edge-pt) image(background) 
              -> image
   

   Draw a red circle on the given image background. The center of the circle should be at the posn center. The edge-pt should be on the perimeter or boundary of the circle.