var mess = new Array('<img SRC="pic20.jpg" BORDER=1 height=150- width=205>','<img SRC="pic21.jpg" BORDER=1 height=150 width=205)>','<img SRC="pic22.jpg" BORDER=1 height=150 width=205>','<img SRC="pic23.jpg" BORDER=1 height=150 width=205>');
var max = mess.length;
var num = Math.floor((Math.random() * max));
document.writeln(mess[num]);