function open_win(nummer)
{
X=nummer
Y="http://www.bwpartner.nl/English/FttHhelptekst.html#"+X
window.open(Y,"_blank","toolbar=no, location=no, directories=no, status=no, menubar=no, scrollbars=yes, resizable=yes, copyhistory=no, width=500, height=170")
}

function doet()
	{
	a=eval(document.myform.a.value)
	b=eval(document.myform.b.value)
	c=eval(document.myform.c.value)
	d=eval(document.myform.d.value)
	e=eval(document.myform.e.value)
	f=eval(document.myform.f.value)
        g=eval(document.myform.g.value)
	k=eval(document.myform.k.value)
	l=eval(document.myform.l.value)
	m=eval(document.myform.m.value) 
        i=((e*100/(e*f/100))/l+(((c-100)/l)/3+((c-100)/2)*k))/12
        j=(d/m+(d/2)*k)/12
        F=(a/1.19-b-i-j-g-(35000/(e*(f/100))))
        F=(Math.round(100*F))/100
        Y=Math.round(F*f/100*e)
	document.myform.marge.value=F
	document.myform.totaalmarge.value=Y
	}