Converted by
Mathematica
June 17, 2001
![[Graphics:../Images/Pratica7_gr_98.gif]](../Images/Pratica7_gr_98.gif)
![[Graphics:../Images/Pratica7_gr_99.gif]](../Images/Pratica7_gr_99.gif)
![[Graphics:../Images/Pratica7_gr_102.gif]](../Images/Pratica7_gr_102.gif)
![[Graphics:../Images/Pratica7_gr_127.gif]](../Images/Pratica7_gr_127.gif)