function calculateVolume(itemNumber) {

	var tempQuantity = eval('window.document.frmcalculator.quantity' + itemNumber + '.value');

	var tempVolumeEach = eval('window.document.frmcalculator.itemvolume' + itemNumber + '.value');

				

	if (tempQuantity > 0) {

				window.document.frmcalculator.elements['volume' + itemNumber].value = parseFloat(tempQuantity * tempVolumeEach);

				window.document.frmcalculator.elements['volume' + itemNumber].value = Math.round(window.document.frmcalculator.elements['volume' + itemNumber].value*Math.pow(10,2))/Math.pow(10,2);

	} else {

		window.document.frmcalculator.elements['quantity' + itemNumber].value = '';

		window.document.frmcalculator.elements['volume' + itemNumber].value = '';

	}

	grandTotal()

}



function grandTotal() {

	var a = window.document.frmcalculator.elements.length;

	var i=0

	var total=0

	for (i=1;i < a;i++) {

		if (window.document.frmcalculator.elements[i].name.substr(0,6) == 'volume') {

			if (!isNaN(parseFloat(window.document.frmcalculator.elements[i].value))) {

				total += parseFloat(window.document.frmcalculator.elements[i].value);

			}

		}

	}

		total = Math.round(total)

		window.document.frmcalculator.elements['TotalVolume'].value = total;

}