var showMode = 'table-cell';
if (document.all) showMode='block';
function toggleVis(btn){
	btn   = document.forms['tcol'].elements[btn];
	cells = document.getElementsByName('t'+btn.name);
	mode  = btn.checked ? showMode : 'none';
	for(j = 0; j < cells.length; j++) cells[j].style.display=mode;
}

var head="display:''"
function doit(header){
var head=header.style
if (head.display=="none")
head.display=""
else
head.display="none"
}