var intTotal

	function calculate(){
	
		strType = document.frmCalc.areaType.value;
		strDepthType = document.frmCalc.depthType.value;
		intA = new Number(document.frmCalc.intA.value);
		intB = new Number(document.frmCalc.intB.value);
		intDepth = new Number(document.frmCalc.intDepth.value);
		
		
		if(strType == "2"){
			intA = intA * 0.3048;
			intB = intB * 0.3048;
		}
		if(strType == "3"){
			intA = intA * 0.9144;
			intB = intB * 0.9144;
		}
		
		if (strDepthType == "2"){
			intDepth = (intDepth * 25)  / 1000;
		}
		if (strDepthType == "1"){
			intDepth = (intDepth * 10) / 1000;
		}
		
		intTotal = intA * intB;
		intTotal = intTotal * intDepth;
				
			
			
			
				
		
		document.frmCalc.total.value = intTotal;
		document.frmCalc.total2.value = intTotal * 0.75;


}
	
	function addArea(){
		if(intTotal != ''){
			window.opener.formField.value = intTotal;
			window.close();
		}
	}