function gotestaa(){
	obj = document.doublecombo;
	blk = "";
	if ( obj.plan.value != blk ){
		link = obj.plan.value;
	}else if( obj.office.value != blk ){
		link = obj.office.value;
	}else if( obj.area.value != blk ){
		link = obj.area.value;
	}else{
		return;
	}
	window.open(link,"_blank");
}