<!--
			
function calcAgg(form) {
    var aggAmt = 0;
    if (form.elements[8].checked == true)
       form.elements[4].value = "4000";
    else if (form.elements[9].checked == true)
       form.elements[4].value="2835";
    for (var i = 1; i <= 3; i++) {
       var parsecheck = "" + parseFloat(form.elements[i].value);
       if (parseFloat(form.elements[i].value) < 0 ||
           parseFloat(form.elements[i].value) == 0 ||
           parsecheck == "NaN") {
          window.alert("Please enter a positive number in each of the " +
                       "four input fields.");
          return false;
       }
    }
    if (form.elements[6].checked == true) 
       aggAmt = (form.elements[1].value * form.elements[2].value *
                 (form.elements[3].value / 12.0) / 27.0) * 
                 form.elements[4].value / 2000.0;
    else 
       aggAmt = (form.elements[1].value * form.elements[2].value *
                 form.elements[3].value / 27.0) *
                 form.elements[4].value / 2000.0;
    form.elements[11].value = formatvalue(aggAmt,7);
    return true;
}

function formatvalue(input, rsize) {
   var invalid = "**************************";
   var nines = "999999999999999999999999";
   var strin = "" + input;
   var fltin = parseFloat(strin);
   if (strin.indexOf("e") != -1 ||
       fltin > parseFloat(nines.substring(0,rsize)+".4"))
      return invalid.substring(0, rsize);
   if (strin.length <= rsize) return strin;
   var rounded = "" + (fltin + 
      (fltin - parseFloat(strin.substring(0, rsize))));
   return rounded.substring(0, rsize);
}

function clearform(form,count,lastElement) {
    for (var i = 1; i <= count; i++) form.elements[i].value = "";
    form.elements[lastElement].value = "";
}

function setDensity(form,density) {
    form.elements[4].value=density;
    form.elements[11].value=" ";
}

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-->