function popUpCenteredWindow(URL,hw,hh,w,h,sb){
var iMyWidth;
var iMyHeight;
var hw // half the window's width
var hh // half the window's height

//gets top and left positions based on user's resolution so hint window is centered.
iMyWidth = (window.screen.width/2) - (hw + 10)//half the screen width minus half the new window width (plus 5 pixel borders).
iMyHeight = (window.screen.height/2) - (hh + 50)//half the screen height minus half the new window height (plus title and status bars).
	var win2 = window.open(URL, "popup","scrollbars=" + sb + ",status=no,width=" + w + ",height=" + h + ",resizable=no,left=" + iMyWidth + ",top=" + iMyHeight + ",screenX=" + iMyWidth + ",screenY=" + iMyHeight)
}