var t=setTimeout("promptVisitor()",105000); //1 minute 45 seconds = 105 000 milliseconds
var p=20; // percentage
function promptVisitor(){if( Math.random()*100<p && getCookie('opt_survey') == ''){onMask();}}
function setNoCookie(){
	offMask();
	var today=new Date();
	today.setTime(today.getTime());
	var expires_date=new Date(today.getTime()+(86400000)); //86400000 ms = 1 day
	document.cookie='opt_survey'+'='+escape('NO')+';path=/;expires='+expires_date;
}
function getCookie(c_name){if(document.cookie.length>0){c_start=document.cookie.indexOf(c_name+"=");if(c_start!=-1){c_start=c_start+c_name.length+1;c_end=document.cookie.indexOf(";",c_start);if(c_end==-1)c_end=document.cookie.length;return unescape(document.cookie.substring(c_start,c_end))}}return""}
function myopen(filename,windowname,properties){mywindow=window.open(filename,windowname,properties);mywindow.self.focus()}