function calcula() {
	var t, t1, t2, t3;
	t1 = ($('#valor1').val() * $('#qtd1').val())
	t2 = ($('#valor2').val() * $('#qtd2').val())
	//t3 = (getElm('valor3').value * getElm('qtd3').value)
	t = t1+t2;
	$('#total').val(t+'.00');
}

function isNumberKey(evt) {
	var charCode = (evt.which) ? evt.which : event.keyCode
	if (charCode > 31 && (charCode < 48 || charCode > 57))
		return false;
	return true;
}