#C3----------------------------------------------
plane p 0 0 0  0 .5 -1 1 0 0
psphere p p 20 
plane p2 0 0 15 0 0 1 0 -1 0
pcone p2 p2 9 7 15
bfuse f p p2
nexplode f f
depouille result f 0 0 1 f_1 12 0 0 30 0 0 1

set square 5536.05