function visibleDiv(id,f){
	var aff=(f==0)?"'hidden'":"'visible'";
	eval("document.getElementById('" + id + "').style.visibility=" + aff);
}
function displayDiv(id,f){
	var aff=(f==0)?"'none'":"''";
	eval("document.getElementById('" + id + "').style.display=" + aff);
}