var mess = new Array(
'<img src="images/ke06_image.jpg" width="409" height="230">',
'<img src="images/ke06_image02.jpg" width="409" height="230">',
'<img src="images/ke06_image03.jpg" width="409" height="230">',
'<img src="images/ke06_image04.jpg" width="409" height="230">');
var max = mess.length;
var num = Math.floor((Math.random() * max));
document.writeln(mess[num]);