procedure bodenplatte;

VAR
x,s,r:real;

BEGIN;

x:=1.5;
s:=0.3;
r:=11;

arcbycenter
	(0,0,r,0,360);
arcbycenter 
	(0,0,r-x,0,180);
arcbycenter
	(0,0,r-x-s, 0, 180);

END;
RUN(bodenplatte);