function form_change(obj){
    if( document.all && navigator.userAgent.search('Opera') < 0 ) property = 'block';
	else property = 'table-row';


	if( obj.value == "1" ) {
		document.getElementById('tr1').style.display = property;
		document.getElementById('tr2').style.display = property;
		document.getElementById('tr3').style.display = property;
		document.getElementById('tr4').style.display = property;
		document.getElementById('tr5').style.display = property;
		document.getElementById('tr6').style.display = property;
		document.getElementById('tr7').style.display = 'none';
		document.getElementById('tr8').style.display = 'none';
		document.getElementById('tr9').style.display = 'none';
		document.getElementById('tr10').style.display = 'none';
		document.getElementById('tr11').style.display = 'none';
		document.getElementById('tr12').style.display = 'none';
		document.getElementById('tr13').style.display = 'none';
		document.getElementById('tr14').style.display = 'none';
		document.getElementById('tr15').style.display = 'none';
	    }


	if( obj.value == "2" )  {
		document.getElementById('tr1').style.display = 'none';
		document.getElementById('tr2').style.display = 'none';
		document.getElementById('tr3').style.display = 'none';
		document.getElementById('tr4').style.display = 'none';
		document.getElementById('tr5').style.display = 'none';
		document.getElementById('tr6').style.display = 'none';
		document.getElementById('tr7').style.display = property;
		document.getElementById('tr8').style.display = property;
		document.getElementById('tr9').style.display = property;
		document.getElementById('tr10').style.display = property;
		document.getElementById('tr11').style.display = property;
		document.getElementById('tr12').style.display = property;
		document.getElementById('tr13').style.display = property;
		document.getElementById('tr14').style.display = property;
		document.getElementById('tr15').style.display = property;
	}
}