var mess = new Array('<img src="images/center-photo.png" alt="" height="339" width="975" border="0">','<img src="images/center-photo-paints.png" alt="" height="339" width="975" border="0">','<img src="images/center-photo-hands1.png" alt="" height="339" width="975" border="0">');
var max = mess.length;
var num = Math.floor((Math.random() * max));
document.writeln(mess[num]);