function SwapImage()
{
   var doc=document, args=arguments;
   doc.$imgSwaps = new Array();
   for(var i=2; i<args.length; i+=2)
   {
      var elem=FindObject(args[i]);
      if(elem)
      {
         doc.$imgSwaps[doc.$imgSwaps.length]=elem;
         elem.$src=elem.src;
         elem.src=args[i+1];
      }
   }
}

function FindObject(id, doc)
{
   var child, elem;
   if(!doc)
      doc=document;
   if(doc.getElementById)
      elem=doc.getElementById(id);
   else
   if(doc.layers)
      child=doc.layers;
   else
   if(doc.all)
      elem=doc.all[id];
   if(elem)
      return elem;
   if(doc.id==id || doc.name==id)
      return doc;
   if(doc.childNodes)
      child=doc.childNodes;
   if(child)
   {
      for(var i=0; i<child.length; i++)
      {
         elem=FindObject(id,child[i]);
         if(elem)
            return elem;
      }
   }
   var frm=doc.forms;
   if(frm)
   {
      for(var i=0; i<frm.length; i++)
      {
         var elems=frm[i].elements;
         for(var j=0; j<elems.length; j++)
         {
            elem=FindObject(id,elems[i]);
            if(elem) return elem;
         }
      }
   }
   return null;
};

function calc() {
	d = document;
	yf = ( d.savings.years.value * 0.000035 ) + 0.001;
	cp100 = d.savings.cylinders.value * d.savings.cm.value * yf;
	cg100 = cp100 * 1.1;
	eco100 = cp100 * d.savings.petrol_price.value - cg100 * d.savings.gas_price.value;
	document.savings.p5000.value = Math.round(eco100 * 50);
	document.savings.p7500.value = Math.round(eco100 * 75);
	document.savings.p10000.value = Math.round(eco100 * 100);
	document.savings.p15000.value = Math.round(eco100 * 150);
	document.savings.p30000.value = Math.round(eco100 * 300);
	return false;

};