function showLayer(whichLayer)
{
	if (document.getElementById)
	{
		// this is the way the standards work
		document.getElementById(whichLayer).style.display = "block";
	}
	else if (document.all)
	{
		// this is the way old msie versions work
		document.all[whichLayer].style.display = "block";
	}
	else if (document.layers)
	{
		// this is the way nn4 works
		document.layers[whichLayer].style.display = "block";
	}
}
function hideLayer(whichLayer)
{
	if (document.getElementById)
	{
		// this is the way the standards work
		document.getElementById(whichLayer).style.display = "none";
	}
	else if (document.all)
	{
		// this is the way old msie versions work
		document.all[whichLayer].style.display = "";
	}
	else if (document.layers)
	{
		// this is the way nn4 works
		document.layers[whichLayer].style.display = "";
	}
}

function layerShown(whichLayer)
{
	if (document.getElementById)
	{
		// this is the way the standards work
		return document.getElementById(whichLayer).style.display == "block";
	}
	else if (document.all)
	{
		// this is the way old msie versions work
		return document.all[whichLayer].style.display == "block";
	}
	else if (document.layers)
	{
		// this is the way nn4 works
		return document.layers[whichLayer].style.display == "block";
	}
	else
	{
		return true;
	}
}

function toggle(whichLayer)
{
	if (layerShown(whichLayer))
	{
		hideLayer(whichLayer);
	}
	else
	{
		showLayer(whichLayer);
	}
}

function handleVis(whichLayer, on)
{
	if (on)
	{
		showLayer(whichLayer);
	}
	else
	{
		hideLayer(whichLayer);
	}
}