function selectbox()

 {
	var s=document.advance_search;
	if(s.make_id.value=="")
	{
	alert ("Please select your make");
	s.make_id.focus()
	return false;
	}

	if(s.model_id.value=="")
	{
	alert ("Please select your model");
	s.make_id.focus()
	return false;
	}
  
	if(s.registration_state.value=="0")
	{
	alert ("Please select your state");
	s.registration_state.focus()
	return false;
	}
 
	 return true;
 
}